Hoffman, Professor of Mechanical Engineering in the University of Nebraska, for his helpful criticisms on the chapters dealing with refrigeration and to Mrs. J. H. Frandsen for help and encouragement in the preparation of the
manuscript.

in buying cream for an ice cream factory Kind of cream required Acidity Free from odors Fat content How to secure high grade cream Education of patrons Inspection and supervision of the

—

—

test

test

test

in

tests

test

tives

I

CHAPTER
The

II

Bacteriology of Ice Cream Bacteria Conditions of life Source of bacteria in

—

—

— What they are — cream ...
ice

19

CHAPTER
The
Care! of

III

Milk and Cream at the Factory — Receiving,

sampling and grading ^Test each patron's shipment Methods of keeping cream in good condition after it has been Cooling without pasteurizing Pasteurization received Effects upon the body and swell of the ice and cooling

—

—

—

—

—

cream

33

CHAPTER

IV

Condensed Milk, Milk Powder, and Homogenized Cream The manufacturing Relation to the ice cream industry The quality of the milk used process of condensed milk Milk: powder Bulk condensed milk Evaporating Use of milk powder To suppleMethod of manufacture Use in ice cream mixture' Homoment the milk supply Objects of homogenizing Process of genized cream

Definition of the Standardizing the Ice Cream Mixture term Importance of standardizing Methods of standardThe Babcock izing By diagram Rule for standardizing Use of special acids test for fat in ice cream

— —

—

—

—

—

—

79

CHAPTER

VIII

Selecting and mixing the Preparing the Ice Cream Mixture For cooked For uncooked mixtures various ingredients How they diff^er from the uncooked mixtures mixtures Preparing and mixing the ingredients Water ices and

—

—

—

—

—

—

sherbets

86

CHAPTER
Cream

IX
in

— Ice creams as defined the pure Classification of Ice food law — Classification of ice creams and ices — Mortensen's classification — Washburn's classification — Larsen and White's classification — The need of a simple system of classification

using caramel and ice cream made according to the formula for Philadelphia ice cream How and when to add the nuts Almond and pistachio ice cream Fruit ice cream made according to the formula for Philadelphia ice cream Selecting and preparing the fruit How and when to add the fruit The use of preserved fruits The use of lemons and oranges A formula which may be taken as the basis for all Neapolitan ice creams Preparing the eggs Kinds of Directions for cooking flavors which may be used How and when to add the flavor Cooling and freezing French cooked cream Tutti f rutti ice cream Nesselrode pudding Manhattan pudding Frozen custard Other Neapolitan formulas Almond pistachio Burnt almond Butter Chestnut Coffee Filbert Royal Fancy molded ice creams and ices How they differ from ordinary ice cream Kinds of Importance of the trade molds Use of special formulas Preparing the ingredients for mousse The cream Flavoring Freezing Formulas
•

CONTENTS maple syrup — Nut

ix

PACE

—

—

—

—

—

—

—

—

—

—

—

— — — — — — —
Ices

—

—

—

—

—

—

—

—

—

—

— — —

— — —

—

—

99

CHAPTER
Water
and Sherbets

XI
ices

—

Sherbets Lactos

— Fruit

granite

— General directions — Water — — Roman Punch — Milk sherbets
122

CHAPTER
Fancy Molded
ice

XII

Ice Creams and Ices Difference between bulk cream and molded ice cream Difference in formula Difference in package For a different class of trade Importance of flavor and color Different colors must harmonize Colors and flavors must harmonize Kinds of fancy molds Brick molds Special molds Preparing Kinds of ice cream used and freezing fancy bricks Ice Preparing and filling the molds cream and sherbet 134

—

— —

—

—

—

—

— —

—

—

— —

—
.

.

CHAPTER
The

XIII

Freezing the mix Freezing Process In the freezer After removal from the freezer Texture and swell of ice cream as affected by the freezing process Time to freeze Speed of dasher Controlling the freezing process The The freezing medium kind of freezer 148

—

—

— —

^ —

—

— —

CHAPTER XIV
Refrigeration — Ice cream making and refrigeration — Refriger— By other means — Meation a transfer of heat — By development and application to chanical refrigeration —
:

Its Location and Equipment Importance of good' location Essentials of sanitary construction and arrangement Light and ventilation Floors Facilities for cleaning up Walls and ceilings Convenience Location of storage rooms and machinery Factory equipment Simple equipment for a small plant Ice Essentials of a good freezer cream machinery Batch mixers Ice crusher Can washer Sterilizer and drier Kettle for Neapolitan ice cream The homogenizer Cream whipper Miscellaneous and special equipment 202 Ice

Cream Factory;

—

—

—

—

—

—

—

—

—

—

— —

— — — —

—

—

.

CHAPTER
Factory Management
efficiency

XVIII
machinery to factory

— Business methods — The use of records — Forms of records — Cost of conducting the business — Keeping track of packing tubs — Increasing sales — The value of advertising — Methods of advertising — The winter trade
.
.

— The

relation of

239

CHAPTER XIX
By- Products and Side Lines
line

— To

utilize surplus

steady

crew

— Side

Importance of carrying a side milk and cream Employment to a lines Butter Sweet cream Fer-

— —

—

—

—

CONTENTS
merited

xi
cheese
.
.

milk

Methods of manufacture

— Buttermilk — Yoghurt — Cottage — Fancy soft cheese
.

—
.

PACE
255

CHAPTER XX
Ice

Cream as a Side Line in the Local Creamery
to

—

Extent cream is manufactured in small creameries Condition under which such a venture will prove profitable Population Competition Advantages which a creamDifficulties to be overcome ery possesses Equipment Simple equipment for a small plant Location of the ma-

—

which

ice

—

— chinery — Profits that may be expected — Cost of material — Value of fat sold as ice sold as butter — Value of fat

problems with which the manufacturer of butter, of condensed milk, or even the whole milk dealer does not have to contend. In the first place, ice cream is a product that
cannot be stored for any length of time.

No

very great

surplus can be carried in storage to meet future demands.

This in
it

itself

not for the fact that the
then,
is

would not be such a serious difficulty were demand for ice cream is variable.
to be able to secure a sufficient supply

The problem,
of the
little

raw material to meet all demands and yet have as surplus cream as possible to be disposed of in some
disposed of in various

other manner.

The surplus sweet cream may be
ways
the surplus and may, in

so that the factory will not have to sustain a loss

on
In

view of these
ficient

facts
all

some cases, realize a profit. and owing to the importance of a
it is

suf-

supply at

times,

better to have a small surplus

rather than a shortage of sweet cream.

The

quality of the cream

is

of utmost importance.

When

received at the factory the cream should have an

acidity of not

more than

0.25 of
I

i

per cent.

It is

not suf-

2
ficient that the

ICE

CREAMS AND

ICES

foreign odors and flavors.
the

cream

will

cream be sweet, but it must also be free from Any abnormal odor or flavor in be imparted to the ice cream and will lower
This
is

the quality of that product.
that

not the only objection

may

be raised against off flavored cream.

are usually associated with a high bacterial content.
bacterial content indicates that the

Off flavors A high

contaminated with

filth,

cream is old, or has been or improperly cared for on the

farm or

in transit.

The
will

cost of transportation and the labor of handling

be greatly reduced if the farmers producing the cream can be induced to skim a fairly rich cream. When received at the factory the cream should contain at least 25 per cent, The advantages of shipping a rich cream are of butter fat.
very apparent. per cent, of butter fat which

vantage to
is

bought according to the it is certainly an adhave the fat concentrated into a small volume, as
is
it

Since the cream

contains,

the transportation charges for a
also

pound of

fat are less.

It

much

easier to ship,

and

will stand transportation bet-

ter,

because a rich cream does not show the effects of bac-

terial action as quickly as thin

smaller
feed.

amount of milk

On

cream since it contains a upon which bacteria account of the waste and greater cost involved in
constituents

handling thin cream, every effort should be
a cream that
is

made

to secure

fairly rich in butter fat.

The means employed

to secure

cream

of the desired

quality will depend somewhat upon local conditions; but
the education of patrons to a higher standard, the inspection

of the source of supply, the grading of cream, and the pay-

ment on

the quality basis will be found

most

effective.

The

condensed milk factories

may be

pointed out as illustrations

of what a consistent policy of education, inspection, and

THE CREAM SUPPLY
grading will accomplish
in the

3

way

of securing a good, clean

raw

material.

Regulating the production of cream.
turer of ice cream should lay

The manufac-

down

tions regarding the production

and regulaand handhng of the milk and
certain rules
effective,

cream purchased and adopt these as a part of the policy of
the concern.

To make
is

such a policy

however,

it

will be necessary to get into closer touch with the farmer.

This

is

a point that

too often neglected.
all

But why build

a sanitary plant and

make

necessary arrangements for

manufacturing and delivering the finished product in a cleanly manner if the source of supply is left unguarded? It will be necessary to educate the patrons to a higher standard, otherwise such a policy will meet with considerable opposition.

Education of patrons.
been published
products,
in temperature
in dairy

Notwithstanding

all

that

has

papers regarding the care of dairy

many farmers do not realize that a few degrees may have a very marked influence upon the
and cream, or that a very
little dirt

quality of the milk

can

carry enough bacteria to lower the quality of a large quantity
of milk or cream.

For

this

reason the factory manager

must

see to

it

that his agents give the necessary instructions

to the patrons in regard to the proper care of milk

and cream

on the farm.
'

As a further incentive to the proper care of milk and cream on the farm, a system of grading should be adopted. Each can of cream should be carefully inspected when it reaches the factory. A knowledge of cream grading should be one of the essential qualifications of the man on the receiving platform.

\/Cream

grading has met with considerable opposition not

4

ICE

CREAMS AND

ICES

only from the cream producers but from many cream buyers as well. This opposition is due largely to the lack of a suitable standard. It is not difficult for the average person to distinguish between very good and very poor cream,

but

when

it

comes

to sorting out the intermediate

grades

there will be considerable difference of opinion because there

no known method of determining the quality of milk or cream by means of rapid and accurate tests. The senses and judgment of the person doing the grading must be relied upon almost entirely. It is best, however, to supplement
is

these with a test for acidity.

Grading according to
is

acidity.

In

many

places cream

graded according to acidity only. This method is very simple but is open to criticism, as cream may be sweet according to the test and still be a second grade cream because
of an undesirable odor or flavor.

Such odors and
if

flavors

may be more
alone
is

objectionable than acidity, and
is

the acid test

used, cream that

off flavor

may

be passed as

a
is

first

grade cream.

Cream grading on

the acidity basis

undoubtedly very imperfect but it is far better than at all. Indiscriminate buying fosters carelessness therefore, some system of grading cream should be

no system
;

employed.
test is to

Until

some

better

method

is

found the acid

be recommended as an aid in that work.

There are a number of different methods of testing milk some of which are quite sensitive but require too much time in operating to be of the greatest value in cream grading. Mann's acid test is to be recommended where quite acfor acidity,

curate tests are desired.
is

The test is given here because it one of the most sensitive and reliable acid tests now in use. The apparatus needed consists of a burette and stand, a 50

THE CREAM SUPPLY
c.c.

pipette, a white cup, a glass stirring rod,

an alkaline

solution of

known

strength,

and an

indicator.

The

burette should be graduated

to o.i c.c.

and should be provided
is

with a pinch cock which
in
its

reliable

operation.

The

pipette
cali-

used

should

be

accurately

brated but should not be drawn
to a very fine point.
is

A white
a

dish

used

so

that

very
be

slight

change in
noticed.

color

may

easily

The
of

alkali solution

in this test is usually tenth

solution

sodium

used normal hydroxide
is

(NaOH).^

The
is

indicator

a

substance that
solution.

colorless in

an

acid solution but red in an alkaline

dicator

is

The purpose of the into show whether the
it

Fig.

the

substance in which

is

placed
of
:

is

Nafis apparatus for rapid determination of the acidity of milk and
I.

acid, alkaline, or neutral.

cream.

To

test

the

acidity

method, proceed as follows then measure out 50 c.c. by means of the

milk or cream by Mann's Mix the sample carefully and
pipette.

Place the

milk or cream to be tested in the white cup and add a few
^ normal solution is a solution that contains one gram equivalent of the active reagent in 1000 c.c. Thus a normal solution of tenth will contain (Na)23 plus (O) 16 plus (H)l=40 grams. normal solution will contain 4 gms. in 1000 c.c. or 0.004 gm in each cubic centimeter and will neutralize 0.009 gffl- of lactic acid (GHoOs). The molecular weight of lactic acid is go, therefore a tenth normal solution will contain 9 gms. in 1000 c.c. or 0.009 gm.

A

NaOH A

in

one cubic centimeter.

:

6

ICE

CREAMS AND
Fill

ICES

drops of the indicator.

the burette exactly to the zero

mark

with the alkaline solution.
little

Add

the solution to the

sample a

at

a time and

stir

thoroughly.

Continue add-

ing the neutralizer until a permanent, but very light, pink
color appears.

The number

of cubic centimeters required to

is found by reading the on the burette. This gives what is called degrees of Calculation must be made acidity according to Mann's test. to convert Mann's degrees into terms of per cent.

neutraHze
scale

tlie

acid in the sample

To

find the per cent, of acid.
is

of the alkali solution
lactic acid.

equivalent to 0.009 of a

Each cubic centimeter gram of
°-^
or 0.018
is

Each cubic centimeter of the neutralizer used
sample will therefore represent

in a

50

c.c.

per cent, of acid.

The

total acidity of the

sample

de-

termined by multiplying the number alkali used by 0.018. For example,
acidity of the sample
is

of cubic centimeters of
if it

requires 8.5
c.c.

c.c.

of

the neutralizer to neutralize the acid in 50

of cream, the

0.018

X 8.5 = 0.153

per cent.

The

factor 0.009 represents the weight of lactic acid neutral-

normal solution of sodium hydroxide. This test when properly carried out vvil} be found very accurate, but it requires so much time in the various manipulations that one of the following tests will be found more satisfactory for use in cream grading. Of
ized by each cubic centimeter of a tenth

these Farrington's Alkali Tablets offer one of the mosj;

rapid and fairly accurate means of testing acidity which

may

be used in cream grading.

Farrington's alkali tablets contain a weighed amount of alkali and an indicator. These tablets must first be dissolved in a definite

amount of

distilled

or soft water.

To

THE CREAM SUPPLY
prepare the solution, place
red because
alkaline.
five tablets in

water and allow them to dissolve.
it

97 c.c. of distilled This solution will be
is

is

The

strength of this solution
i

such that each cubic centimeter will neutralize o.oi of

per

Fig.

2.

Apparatus used in Farrington's acid
test.

cent, of acid in 17.6 c.c. of milk or cream.
difficult to

The

test is

not

operate and no calculation

is

necessary to inter-

pret the results.

To make

the test, measure into a white cup 17.6

c.c.

of the milk or cream to be tested.

Rinse the pipette with clear water and add the rinsings to the sample in the cup. Place the alkali solution in a burette or graduated glass cylinder so the amount used may be quickly determined. Add the solution to the milk or cream a little at a time until a permanent pink color appears. When a very light pink
color appears it indicates that all of the acid in the milk has been neutralized by the alkali in solution. Find the number

of cubic centimeters used.

As

each cubic centimeter of the

8

ICE

CREAMS AND
i

ICES

solution neutralizes o.oi of

per cent, of acid, the acidity

may
97

be read in per cent,

direct.

For example, there were
If,

c.c.

of the solution in the cylinder at the beginning.

after adding

enough of

this to the
it

acid, there are "jy c.c. left,
alkali.

sample to neutralize the required 97 TJ or 20 c.c. of

—

As

each cubic centimeter neutralizes

.01
i

of

i

per

cent, of acid,

20

c.c.

are equivalent to 0,20 of

per cent, of

acid in the sample.
It

takes a

little

time for the tablets to dissolve, so a

quantity sufficient for one day's wfork should be prepared

way there is no delay and the testing for done very quickly. These alkaline tablets may be used in another and more rapid test for acidity which is used especially for cream grading. The apparatus required in this rapid test consists of a white cup and twO' small dippers of equal volume. The dippers should hold about 20 c.c. and must be of exactly the same capacity. In making the test an alkali solution is first prepared by
each day.

In this

acidity can be

dissolving eight Farrington tablets in eight ounces of dis-

given volume of

This gives a solution of such strength that a it will neutralize o.i of i per cent, of acid in an equal volume of milk or cream. That is, if, when we measure out 20 c.c. of milk or cream in the white cup and
tilled

water.

add to
pink,
it

it

20

c.c.

of the tablet solution, the mixture remains
i

indicates o.i of

per cent, of acid or

less.

As
is

these

operations

may be

carried out very quickly this test

par-

ticularly adapted to

cream grading. As each lot of cream is received, take out a dipperful and pour it into the white cup. With the other dipper add an equal quanitity of the alkali solution and mix the two bv
giving the cup a rotary motion.
If the color disappears,
it

THE CREAM SUPPLY
indicates that there is
in the sample.

9

more than

o.i of

i

per cent, of acid
alkali,
is

Add
it

another dipperful of

color remains,

indicates that the acidity

and if the below 0.2 of i

Fig.

3.

Apparatus used for rapid estimation of the acidity of milk and cream.
disappears,
it

per cent.
is

;

but

if it

indicates that the acidity

over 0.2 per cent, and more alkali solution must be added. The acid standard. Where a standard of say 0.25
is

per cent, acid

adopted as the

maximum amount

for a

first

grade cream, the operations can be simplified by making the
dipper used in measuring the alkali solution two and onehalf times as large as the dipper used for the cream.
is, if

That

the cream dipper holds 20 c.c, the dipper used in measc.c.

uring the alkali solution should hold 50

If,

upon mix-

ing the cream and alkali solution in these proportions, th^

lo

ICE

CREAMS AND ICES

it indicates an acidity in excess of the maxigrade cream. If the person receiving the cream understands these tests, they will prove quite valuable aids in determining the quality of the various lots of cream. Prices paid. To obtain the best results from a proper

color disappears,

mum

for

first

system of cream grading, however, there must be a graduated scale of prices paid for cream.

A

first

grade cream

should

command

a better price because of the greater care

which the farmer must exercise in its production. Ice cream factories, as a rule, do pay a higher price for the cream which they buy. In view of this fact they should demand a product that meets all their requirements and that will enable the ice cream manufacturer to comply with the stringent regulations of the board of health. Where this
system of personal supervision of the source of supply
with a system of grading and payment according to quality has been adopted, the results, as a rule, have been highly
satisfactory.

The

experience of some manufacturers shows

problem of securing better cream cream maker can secure the grade of cream desired by adopting the proper means to obtain it. Testing the purity of milk and cream. Another method of regulating and controlling the equality of the raw material Is by means of tests for purity. The purity of a sample of milk or cream may be detennined by a sediment test or by a fermentation test. The sediment tests show approximately the amount of insoluble or suspended impurity in a sample. The fermentation test will give some idea as to the kinds of bacteria that are most active in the
that
difficult the

however

may appear

to be, the ice

sample.
tion test
;

It requires

much more time

to coinplete a

fermenta-

so for rapid determinations the sediment tests are

usually employed,

THE CREAM SUPPLY
the

II

Sediment tests. There are two methods of determining amotmt of sediment that a giVen sample may contain.
first

The
for

metliod

is

a special

form of
minutes.

test

by placing a sample of milk or cream in tube and centrifuging at high speed

ten

The
is

sediment

which

a

heavy material

will

be

deposited in the bottom
of the tube where
it

may

be

examined and the quantity and nature of

the impurity determined.

A

more rapid but somewhat less accurate meth^ od is by means of filtering.

The
this

filter

test.

In or

test

a
of

measured
milk

quantity

cream
cotton

is filtered

through
paper.

or

filter

The sediment which
is

the
Fig.

milk or cream contains
deposited upon the
fil-

ter.

The
of

quantity
the

and

nature

impurity

An Electric Centrifuge for 4. determining the amount of suspended impurity in milk and cream.

be determined with accuracy by a careful examination of the filter. It must be remembered, however, that a large part of the dirt that finds its way into milk is soluble and therefore will not
fair

may

be caught upon the

filter.

Such

filth is

just as objectionable
filth

as the insoluble dirt.

It is

the fact that

carries large

;

12

ICE

CREAMS AND ICES
into the milk that

numbers of bacteria

makes

it

so dangerous.

The presence or absence of

these bacteria may, for practical
test.

purposes, be determined by means of a fermentation
furnishes a convenient

The Gerber fermentation

test

method for

Fig.

S.

The

The
Progress

Wisconsin sediment test.

Dirt

method of

Tester, showing operation.
is

poured into cyhnder (a), on the bottom of which is
a perforated cap (b)
this and the dish (c) a disc of cotton batting is placed through which the milk passes into the receptacle (d).

The milk

examining the purity of milk or cream by determining the nature of the change brought about by fermentation.
siderable

between

The
time

test requires con-

but

is

its completion very simple and requires but

for

little

apparatus.

The apparatus needed consists of a number of glass tubes and stopwater bath, and a
especially

pers, a rack for holding the test tubes, a

thermometer.

The apparatus may be purchased

THE CREAAI SUPPLY

13

for fermentation tests, or ordinary sample tubes and other

apparatus found in almost any factory will answer the purpose.

To make

the

test,

fill

each tube about two-thirds

full

of

the different samples of milk or cream and place them in a

rack in an upright position.
placed in a water bath.
F.

The

tubes and rack are then

The

vessel should be about two-

thirds full of water at a temperature of 100° F. to 104°

This temperature must be maintained

all

the while.

At

the end of six hours the tubes are removed one at

a time, shaken gently and the appearance, odor and flavor of

each sample noted.
detected

By keeping
is first

the tubes tightly stoppered

during fermentation, the odor of the sample will be easily

when

the stopper

removed.

Any

objection-

cream is sure to cause trouble if that cream is used in the manufacture of ice cream. The samples are returned to the water bath and fermented for six hours longer and again examined. The tainted and impure samples may be easily detected by their abnormal coagulation and odor. Fresh milk or cream that has been properly handled should not coagulate in less than 12 hours when kept under these conditions, nor should it show any indications of abnormal fermentation. If a sample is found which undergoes no change when subjected to these conditions for a day or two,
able odor in the
it

The most common

should be tested for preservatives. preservatives used in milk are for-

maldehyde or solutions containing formaldehyde. These " solutions are sometimes known as " f reezine " or " iceline and by various other trade names. A test for these preservatives which is fairly good and commendable for its simplicity is made by placing 10 c.c. of

14

ICE

CREAMS AND

ICES

milk and 5 ex. of water in a test tube and mixing thorNext add 5 c.c. of commercial sulphuric acid, pouroughly.
ing the acid into the tube in such a

way

that

it

does not mix

with the milk but forms a distinct layer under the diluted
milk.
If

formaldehyde

is

present, a violet color will ap-

pear at the junction of the milk and the acid.

This

test will

show
tive
is

the presence of formaldehyde only

when

the preserva-

present in quite large amounts.

A

test that will
is

of formaldehyde

show the presence made by placing 5 c.c.

of only a trace

of milk and 5
c.c.

c.c.

of water in a porcelain dish.

To

this

mixture add 10

of

hydrochloric acid and a few drops of ferric chloride solution

(FeClj). Heat the mixture slowly and if formaldehyde is present a violet color will appear. These tests with the sediment and fermentation tests will be found useful in controlling the quality of the milk and cream received. To fully understand the fermentation test, however, a knowledge of the elements of bacteriology will

be of considerable value.

THE CREAM SUPPLY

15

United States Department of Agriculture
BUREAU OF ANIMAL INDUSTRY,
DAIRY DIVISION

and pleasant flavor and odor, score perfect Deduct for objectionable flavors and odors according to conCOMPOSITION

ditions found.

If 20 per cent, fat or above, score perfect (25).

Deduct

1 point for

each one-half per cent, fat below 20.

BACTERIA
Less than 10,000 per cubic centimeter Over 10,000 and less than 25,000 per cubic centimeter. Over 25,000 and less than 50,000 per cubic centimeter. Over 50,000 and less than 73,000 per cubic centimeter. Over 75,000 and less than 100,000 per cubic centimeter.
20 (perfect).
19
18 17
.

.

.

.

16

Deduct

1 point for each 25,000

above 100,000.

When

further deduction should be

an unusually large number of liquefying bacteria are present, made according to conditions found.
ACIDITY

If 0.2 per cent, or below, score perfect (5).

Deduct
is

1

point for

each 0.01 per cent, above

0.2.

(If JMann's test

used, discontinue

adding indicator on

first

appearance of a pink color.)

APPEARANCE OF PACKAGE AND CONTENTS
package is clean, free from metal parts, and no foreign matter can be detected in the contents, and physical condition of product is good, score perfect (10). Make deductions according to conditions.
If

THE CREAM SUPPLY

17

United States Department of Agriculture
BUREAU OF ANIMAL INDUSTRY
DAIRY DIVISION

SCORE CARD FOR MARKET MILK
Exhibitor

Address

.

NUMERICAL SCORE
Flavor. Composition Bacteria,
40. 35.
20.

Acidity,
5.

Appearance of Perfect package and
contents, 10.

score,

100.

Judge's score

DESCRIPTIVE SCORE

Flavor

Composition

Bacteria

Acidity

Package and
contents

Excellent.

Perfect.

Perfect.

Perfect.

Perfect.
cent.

Good.
Fair.

Fat
. . .

Total
.per cent.
Liquefiers
.

.

.

.per

Foreign
matter.

Bad.
Flat.
Bitter.

Solids not
fat.
. .

Metal parts.
Unattractive.

.

.per cent.

Weedy.
Garlic. Silage.

Manure. Smothered. Other taints

Remarks
Date
(Signature)
Judge.

. .

i8

ICE

CREAMS AND

ICES

DIRECTIONS FOR SCORING
FLAVOR
If rich, sweet, clean,

(40).

and pleasant flavor and odor, score perfect Deduct for objectionable flavors and odors according to conCOMPOSITION

ditions found.

above and 8.5 per cent, solids not fat or above, score perfect (25). Dededuct 1 point for each one-fourth per cent, fat below 4 and I point for each one-fourth per cent, solids not fat below 8.5.
If 4 per cent, fat or

BACTERIA Less than 10,000 per cubic centimeter Over 10,000 and less than 25,000 per cubic centimeter. Over 35,000 and less than 50,000 per cubic centimeter. Over 50,000 and less than 75,000 per cubic centimeter. Over 75,000 and less than 100,000 per cubic centimeter.
30 (perfect).
I'.i

.

.

IS 17
.

.

16

Deduct

1 point for

each 25,000 above 100,000.

When

further deduction should be

an unusually large number of liquefying bacteria are present, made according to conditions found.
ACIDITY

If 0.2 per cent, or below, score perfect

(5).

Deduct

I

point for
dis-

(If Mann's test is used, each 0.01 per cent, above 0.3 per cent. continue adding indicator on first appearance of a pink color.)

ArPEARANCE OF PACKAGE AND CONTENTS
clean, free from metal parts, and no foreign matter can be detected in the contents, score perfect (10). Make deductions according to conditions found.

If package

is

CHAPTER
THE BACTERIOLOGY OF

II

ICE

CREAM

Bacteria are the lowest and simplest forms of plant life, each organism consisting of a single cell. There are three

groups into which bacteria may be divided according to form. These are the bacilli or rod-shaped bacteria, the cocci or ball-shaped bacteria, and the spirilla or spiralshaped bacteria. These names apply to the form of the individual
cells.

The

individual cells

may grow

in clusters, in

chains, or in
istics

some other

definite form.

These charactercells first in-

aid in identifying the organism.
of bacteria.

Growth

In their growth the

new cell wall is formed, dividing the original cell into two new organisms which are called daughWhere the division of the cells takes place in one ter cells. plane continually, the bacteria will form chains. The increase in size.
dividual cells are so small that the
definitely identified

A

by

its

general form.
Bacteria

organism cannot be Its food habits

must be taken
Saprophytic

into consideration also.

bacteria.

feed

upon

a

great
is

variety of materials.

In most cases, howe^'er, their food

confined to organic substances, such as sugars, proteids, fats

and other
unable to

inert material, but

some forms may feed upon

either living or

dead tissues. Most bacteria, however, are feed on the living tissues because the living organ19

20

ICE

CREAMS AND ICES

f\

B

Fig.

7.

Forms

of Bacteria,
to

which enable them
lactic acid bacteria,

gether

in

chains,

(a) Bacteria with Iiairlike appendages in water or milk, (b) Typical (c) Bacteria of the coccus type, hanging to(From (d) Bacteria of the coccus type.

swim about

Fanners' Bulletin 490.)

THE BACTERIOLOGY OF
ism has the power to
tissue after
it

ICE

CREAM
it

21

resist bacteria.

If placed

on the same
very readily.

is

dead, they will feed upon

Bacteria of this type are
Parasitic bacteria.

ing tissue of plants or
this class

known as saprophytes. The bacteria that feed upon the livanimals are known as parasites. To

belong the disease producing bacteria. Both the and saprophytic forms may be carried in milk but very small numbers of parasitic bacteria are far more objectionable than large numbers of bacteria of the saprophytic
parasitic
type.

habits of bacteria are varied, but certain organisms are responsible for peculiar changes which take place in the fermenting substance. For the person handling dairy products, a knowledge of the food habits of
specific

The food

the most

common forms

of bacteria

is

of considerable im-

portance in bacterial control.
certain products in the

The

action of a particular

class of bacteria will manifest itself
f ennenting

mass.
will

bacteria that feed on milk sugar will

by the formation of For example, the produce acids, other
cause putrefaction.

forms feeding on proteid material

A

general idea of the nature of the active organism can be

obtained by observing the products formed in the process
of their growth and multiplication.
teria

For convenience, bac-

may be

classified

according to their food habits into

fermentative and putrefactive organisms.

Fermentative bacteria are those that bring about the complex changes, such as acid production from a splitThe acid producers are normal ting up of the milk sugar. milk bacteria that are sure to be present even under the most sanitary conditions. It is only when they have increased enormously that their presence is objectionable. The production of acid renders the milk and cream unfit for
less

22

ICE
;

CREAMS AND ICES

consequently, the proper means must be employed to hold the acid producers in check. The gas producing bacteria are usually associated with filth. The presence of these organisms is therefore much more objectionable than the acid producers. Acid fermentation frequently accompanies the gassy fermentation but there is no mistaking the work of the gas producing organisms. The milk and cream may become entirely unfit for

use in ice cream

food.

The
but

fat-splitting bacteria are not

so well understood

some bacteria have the power of splitting up fat into glycerin and free fatty acid. This cleavage of fats is due to an enzyme secreted by the bacteria and is
it is

known

that

probably hydrolytic in nature.
milk, and allied substances
is

The

rancidity

of

butter,

thought to be due to the action

of bacteria belonging to this class.

Putrefactive bacteria belong to that class of organisms

on proteid matter. Substances such as meat, eggs, and albumen are subject to putrefactive changes when acted upon by bacteria. The action of these organisms when carried to a point where the results of their growth are noticeable renders the substance unfit for food. Under some circumstances the products of the decomposition of proteids are poisonous. Ptomaines are substances of this sort. The toxic substances sometimes developed in dairy
that feed
casein,

products

may

be of this class

also.

Ice cream poisoning.

The

so-called ice
in

cream poisons

may

be metalHc compounds formed

milk or cream that

has been shipped in improperly tinned or rusty cans.

The

formation of poisonous chemical substances from metals was at one time the popular explanation for food poisoning.
Later investigations, however, show that where poisons are

THE BACTERIOLOGY OF
found
in

ICE

CREAM

23

food substances they are usually the cleavage prod-

ucts of bacterial action

upon proteid matter. Ptomaines, the poisonous substance formed in meat, and tyrotoxicon, a poisonous substance sometimes found in stale cheese, are of
this class of

degenerate proteids.

Other proteid substances

same decomposition. Such products as bakery cream puifs, which sometimes contain large amounts of egg albumen or gelatine, are regarded as dangerous by some people because of the fear that these products may not be fresh and the proteids which they contain are subject to decomposition. The so-called ice cream poisons belong to a class of protein compounds allied to ptomaines and tyrotoxicon but are by no means confined to ice
are subject to this

cream.

sometimes follow the consumption when a person is in an overheated condition have been mistaken for ice cream poiresults that

The bad

of large quantities of ice cream
soning.

Cases of true ice cream poisoning are not as com-

people think. However, as ice cream is a dairy product containing large amounts of proteid substance, which under insanitary conditions may break down and
as

mon

many

form toxic compounds,
practiced at
all

the utmost cleanliness should be

times.

The ptomaines and allied substances must not be confused with the bacterial toxins, which are secreted by certain bacteria irrespective of the medium in which they grow.

The ptomaines

are cleavage products of the substance upon which bacteria feed, whereas the bacterial toxins, in the specialized meaning which the term has acquired, are soluble,
secretory products of the bacterial
cells. ^

of ptomaines takes place in dead proteid matter but

The formation many
185.

^"A

Text Book of Bacteriology," Hiss and Zinsser, page

2

24

ICE

CREAMS AND
cell

ICES
tliat

of the bacteria that secrete toxins or

contain poisonous

bodies in the bacterial

are able to attack living tissues.

These are the disease producing bacteria. Disease bacteria. It is a well known fact that disease can be spread by infected milk. The disease organisms that find their way into milk may come from the cows producing the milk or they may be introduced from diseased attendants
handling the milk or cream.
tion

The

possibilities of

contamina-

from these two sources and also the contamination from improper sewage disposal and polluted water must be careSuch diseases as tuberculosis, fully guarded against. typhoid fever, scarlet fever, and diphtheria may be spread over a wide territory by milk and cream. According to
Conn, the tubercle bacillus does not multiply in milk but
typhoid bacteria are able to increase in milk under favorable
conditions.

Conditions that affect the growth of bacteria.
milk and other dairy products

Since

may

furnish food for

many

different kinds of bacteria, the subject of bacterial control
is of considerable importance to all who are engaged in any branch of dairying. The fact that milk sometimes contains

toxic substances or disease germs

mean
pear

that the presence of poisons

must not be construed to and disease germs is the
Particular bacteria ap-

rule or even a

common

occurrence.

when

the

conditions under which the

substance

is

handled are such that a particular organism finds access to But after the organisms have been introthat substance.

duced they may flourish or die, increase or decrease in numbers and activity according as the conditions are favorable or unfavorable to their growth and multiplication. The conditions
~

which

affect the life

and

activity of bacteria are food,

"

Dairy Bacteriology," Conn,

pp. 91

and

loi.

THE BACTERIOLOGY OF
moisture, light, chemicals and heat.

ICE

CREAM

25

The growth

of bacteria

can be controlled by varying these conditions upon which their multiplication depends.

Food

for bacteria

must be
the

in solution
cell.

before

it

can be abis

sorbed or

made use of by

When

the food

not in

perfect solution, such as the casein in milk, the bacteria
secrete a digestive substance,

known

as an enzyme, which

breaks
is

down

the complex and insoluble substance into a

Milk sugar, being in solution, by bacteria and converted into lactic acid, hence souring is one of the most common fermentations that takes place in milk and cream. In addition to being soluble, the material must be in the proper degree of dilureadily attacked
tion.

simpler and soluble form.

Moisture. Soluble substances that undergo rapid fermentation in dilute solutions are not attacked by bacteria when the substance is in concentrated form. For example,
dilute sugar solutions

undergo fermentations very

readily,

but concentrated sirups are not readily acted upon by bacteria. study of the composition of milk shows that it

A

contains an abundance of food in about the proper dilution
for bacterial growth.

Light.
terial

Even where other
will
is

conditions are favorable, bac-

growth

Direct sunlight
their best

be checked or even destroyed by light. fatal to bacteria. The organisms make
;

growth in moist, dark places hence, the factory should be light and as dry as possible. In controlling the growth of bacteria in dairy products, however, exposure to light would have little or no effect upon the bacteria consequently, other measures must be adopted. Except in the manufacture of condensed milk and milk powder, it is impractical to in any wise affect the bacterial growth by alter;

Stronger chemicals which destroy the bacterial cell The strong chemicals such as corare called disinfectants.
rosive sublimate,

formaldehyde,

etc.,

are also antiseptics

when very

Chemicals cannot be used in controlling the growth of bacteria in milk and cream for the reason that these substances are injurious to the health of the consumer.
dilute.

Antiseptics and disinfectants

may

be applied as washes or
etc.,

sprays to floors, sewers, waste cans,

should the plant

become
Heat.
trolling

infected with bacteria which cause

some abnormal

fermentation.

The

only safe and satisfactory means of con-

the growth of bacteria in milk or

regulating the temperature.

The

rate

at

cream is by which bacteria
It

multiply in milk and cream varies with the temperature.
is

therefore possible to control the growth of bacteria in
its

milk without altering

normal composition and without the

addition of any dangerous clicmical substances.

Effects of low temperatures. Most forms of bacteria grow most rapidly at a temperature of about 90° F to 98° F. As the temperature decreases the growth of the bacteria is retarded until at very low temperatures all growth

may

cease.

peratures.

The cell life is not destroyed at low temThe organism lies dormant until conditions again

become favorable for its growth. Effects of high temperatures,

An

increase in tempera-

:

THE BACTERIOLOGY OF
ture,

ICE

CREAM

27

on the other hand, may

at first increase the activity

of the organisms.

As

the temperature continues to increase,
is

the growth of the cells will be checked until a point

reached A\here

all

growth

stops.
life

A

further increase in
cell.

temperature will destroy the
stroyed,

of the

The thermal
cell life is

death point, the temperature at which the
varies

de-

somewhat with

different

bacteria.

Some

forms are more resistant to high temperature than others. The thermal death point will also vary with the length of time the organism is exposed to the temperature. Under
most conditions a temperature of 140° F. for 20 minutes
is

sufficient

to

destroy the

life

of

the

cell.

At higher
less will

temperatures the time of exposure decreases, until at very

high temperatures an exposure of one minute or
sufficient to

be

destroy vegetative

cells.

Pasteurization.
terial life

are

The effects of high temperatures on bacmade use of in the process known as pasteuris

ization.

In the pasteurizing process, the aim

not

to

milk or cream but to destroy most of the bacteria present without imparting a cooked flavor or otherwise altersterilize the

ing the flavor, appearance, and properties of the substance.

Pasteurized milk

is

not sterile and unless

it is

properly taken

care of after pasteurization, will undergo fermentation in
the course of a very short time.

Spores.
are quite

The fermentations
difficult to destroy.

that take place in the pas-

teurized milk are due largely to the bacterial spores which

The
station

following extract from Bulletin

134 of the Iowa

shows the effect of pasteurization and low temperatures upon the bacterial content of cream " After pasteurization, however, the practical ice cream niaker considers it necessary to store the cream so that it

28

ICE

CREAMS AND

ICES
yield.
is

will regain its viscosity

and give a suitable

This
is

in-

troduces the question of whether or not there
in bacteria

an increase
conIf the

during this period.

A

two-day period
results obtained

sidered suitable for holding the pasteurized cream.

by Conn and Esten with milk are applicable to cream, no
increase

would be exas

pected during this time,

inasmuch

cream

is

usually stored at a tem-

perature close to 32° F.

by

immersing

in

ice

water.

Bacterial counts

were made from time to time and the results obtained are
Fig.
8.

shown

in the

In

Typical rod-shaped Bacteria. some of these the spores are
as

shown

clear

areas.

(From

table on page 29. " This table shows that

Fanners" Bulletin 490.)

cream

can be held at about 32° F. for a num-

ber of days without an increase in the

number of

bacteria

which develop on plain agar at 98° F. It may be objected that holding cream in bottles differs considerably from holding it in quantities as is done under practical conditions, but the data given later show that up to four days, at least, there was no increase of any importance in cream stored in tengallon cans and in the work reported the cream was at times
temperature as high as 37° F." Sources of bacteria in ice cream. Under ordinary conditions the most of the bacteria in ice cream will be those introduced with the cream and milk. If these substances are
at a

. .

THE BACTERIOLOGY OF

ICE

CREAM

29

BACTERIAL CONTENT OF PASTEURIZED CREAM AT DIFFERENT AGES
Time
of Test After

Sample

Pasteurization

Immediately Days, 1
. . .

2

4
5

6
7
.

.

.

.

S.

.

.

.

9
10 11 12
13

14...
15

24

30

ICE

CREAMS AND

ICES

THE BACTERIOLOGY OF
cream.

ICE

CREAM

31

known

purity.

Great care should be used to select gelatin of The importance of this is shown in the folstation. of ice

lowing table taken from Bulletin 134 of the Iowa
Bacteria in

1 c.c.

Sample Number
1

Bacteria per

gram

cream due

to gelatin

32
ice

ICE

CREAMS AND
it

ICES
be necessary to reto the

cream well packed so that

will not

turn unsold ice cream.
factory
is

The

ice

cream when returned

usually very soft or even in a melted condition.
If the

In this melted ice cream the bacteria grow rapidly.

manufacture has been pasteurized, the fermentations taking place in the melted ice cream are not likely to be of an acid nature, because of the destruction

cream used

in its

of the lactic acid bacteria in the pasteurizing process.
bacteria present in the old ice

The

cream are more apt to be of
It

the type that feed

upon

proteids.

has been pointed out

that the cleavage products of proteids are sometimes poisonous.

the old ice cream
if

Hence, the proteolytic fermentations taking place in may be of a dangerous nature, particularly

the ice cream contains a poor grade of gelatin. Unclean utensils introduce into the ice cream large numbers of bacteria of the most undesirable sort. Every pre-

caution should be taken to have

all

utensils properly cleansed

Shipping cans having deep crevices along the seams or roughened places, due to improper tinning on the inside, are very difficult to keep clean. Such cans should be retinned and the seams flushed with solder. The
sterilized.

and

Hot and cold water for washing and rinsing must be available at all times. Sterilizing may be done with hot water but a steam jet is more satiscans will then be easy to clean.
factory.

With

the proper facilities for cleaning and steriliz-

ing utensils, the

number of

bacteria in ice cream,

coming

from the

utensils,

should be very small.

CHAPTER

III

THE CARE OF MILK AND CREAM AT THE FACTORY
The proper handling
reaches the factory
business.
is

of milk and cream as soon as

it

of utmost importance in the ice cream

Each can

of inferior cream received, or allowed

to spoil after reaching the factory,

means a cut

in the profits

of the business.

In order to prevent losses of this sort and

cream as well as the some provision must be made for receiving, sampling, and grading the raw material as it comes to the factory. The sampling and grading must be followed by thorough pasteurization and cooling to
to insure the keeping qualities of the

purity of the ice cream

made from

it,

insure the best results.

Receiving.
the factory
it

As each shipment

of milk or cream reaches

should be weighed,

sampled, and graded.

Each

patron's shipment should be weighed separately and

tested for butter fat by the

may be made on
basis
is

Babcock method, so that payment Payment on this more businesslike than the old method of buying
the butter fat basis.

cream at so much per gallon. It also prevents losses to the factory and at the same time does exact justice to each patron, provided the sampling and testing are properly
done.

Sampling. Each can of milk or cream should be thoroughly stirred before the sample is taken. The sample may
33

34

ICE

CREAMS AND

ICES

be taken with a long-handled sample dipper, with a milk thief, or a McKay sampler, if a composite sample is to be
taken.

For milk
test
is

tests a

composite sample

may

be taken,

and the
sample

a

made two or three times a week. sample made up of small amounts from a number

A

composite

of milk taken of shipments.

f

Such a sample should represent and proportionate amount of the whole.
the average quality

This system of sampling
satisfactory

is

quite

for

milk.

For

cream,
to

it is

much more

difficult

get

even a fairly accurate

composite sample, because the
viscosity of the
difficult to

cream makes it measure out an exact
slight variation in

amount.

A

A

3

the

amount taken

from

one

shipment

may
of

introduce quite
butter

an error on account of the high
percentage
Fig.
10.

fat

in

Types

of

Samplers, '(a) Combined dipper; (b) dipper and stirrer; (c)

Milk Sample

For this reason each patron's cream shipment should
cream.
be tested separately.

The method of cream for fat involves no great variation from the method followed in testing The only precautions that need be mentioned here milk. are the weighing of the samples, manner of reading the test, and the temperature at which the test is read. It is necessary to weigh into the test bottle the exact amount of cream necessary for testing, because a pipette will not deliver an
McKay
Sampler.

Testing.

testing

CARE OF MILK AND CREAM AT FACTORY
exact amount.
is variable,

35

In the

first place,

the fat content of cream

and the

specific gravity of the

cream varies with

the fat content.

More

or less air

is

also incorporated with

the cream in passing through the separator and cannot es-

cape on account of the viscosity of the cream.

On

account

The Torsion
of this viscosity

Balance.

more cream adheres to the inside of the For these reasons a fair test cannot be made without weighing the exact amount of cream. For this purpose quite a sensitive balance must be used. All the
pipette also.

other operations of the test are the same, except in the read-

ing of the fat column.

36

ICE
The proper

CREAMS AND
It will

ICES

points from which to read cream tests
be noticed that the milk

are illustrated in Fig. 13.
tests are

read from the extreme bottom of the fat column
top,

to the

extreme

whereas the cream
difference
is

test is

read from

the bottom of the fat column to the bottom of the meniscus.

The reason

for this

that

in

a whole milk

sample there are some fat globules too small to be separated

Fig.

12.

The new Fairbanks
;

scale.

by centrifugal force therefore, the fat which is not separated is compensated for by giving the fat column a more liberal reading. In reading either milk or cream tests care must be exercised to have the tests at the correct
temperature.

The temperature
140°
F.

at

which these

tests should

be read

is

Since the fat column will contract or expand

CARE OF MILK AND CREAM AT FACTORY

37

with a change in temperature, correct readings will not be obtained if the temperature is much above or below 140° F. This is particularly true of cream because of the
greater volume of fat which
it

contains.

For more

detailed

=:a

^ m
1^

Fig. 13-

Showing the points from which milk and cream tests should be measured.
is

information on testing milk and cream the reader
ferred to

re-

some

special

work on
"

that subject.^

After receiving,
1

sampling,

and grading the milk and
Its

Farrington and Woll's

Testing Milk and

Products."

38

ICE

CREAMS AND ICES

CARE OF MILK AND CREAM AT FACTORY
cream,
the

39
as

next

consideration

is

to

prevent

as

far

possible the increase of bacteria in the milk or
it is

used.

As

ice

cream before cream factories usually pay a price some-

what in advance of the regular butter fat price, every can of cream that sours means quite a loss to the factory. To be prepared for any increased demand for ice cream, the manufacturer must carry a supply of sweet cream on hand.

Continuous Pasteurizer.

How
ties

large this supply should be will depend upon the size
facili-

of the regular trade, the capacity of the plant, and the
for handling and storage.
facilities

Where

for pasteurization are

wanting and

storage facilities are limited the reserve cream supply can

Under such conditions the cream must be cooled as quickly and as thoroughly as possible and held The better method, however, is to at a low temperature,
not be very large.

40

ICE

CREAMS AND

ICES
it

pasteurize and cool the cream before placing

in

the storage

rooms.

In the smaller establishments, which cannot afford

to install a pasteurizer, the

cream may be pasteurized

in

ordinary milk cans by placing them in hot water.

The

cream should be stirred to insure uniform heating. temperature of 140° F. to 145° F must be maintained for
about 20 minutes.

A

The

process of pasteurization consists in heating the milk

Fig. 16.

The Progress

Barrel Heater.

or cream to a temperature sufficiently high to destroy

all

the vegetative cells of bacteria, yeasts, and molds, and then

cooling quickly to a very low temperature to inhibit the growth of spores which are not destroyed at the temperaThere are two methods tures employed in pasteurization. of pasteurization, known as the continuous method and the intermittent method.

CARE OF MILK AND CREAM AT FACTORY
The continuous method.
stant inflow

41

In this method there is a conand discharge of the milk or cream. In these machines the milk or cream is subjected to a very high tem-

perature for a very brief period of time.
therefore

This system

is

Rapid heating is accomplished by passing the milk or cream over the heated inner
wall of the pasteurizer in a very thin sheet.

known

as " flash heat."

The time during

which the milk or cream is subjected to the high temperature is very brief. In most cases a temperature between 170° F. and 180° F. for from one to i^ minutes is employed. The advantages claimed for the continuous method are greater capacity and greater efficiency. Greater capacity is claimed for these machines because there is a continuous inflow and discharge of the milk or cream. This continuous operation makes it necessary to heat higher because the milk or cream is exposed to the
heat for a very short time.
increase in temperature
teria.
It is also

The advantage claimed
is

for

rapid and high heating or " flash heat "
is

that a very sudden

more

effective in destroying bac-

claimed that

many more

of the spore bac-

teria are destroyed

by this system, because the heat is raised so rapidly that the organism is destroyed before it is able to pass into the spore state. When properly handled and so
regulated that
all

of the milk or cream' passing through the

heated to the desired point, these machines are very efficient. The machine is not automatic, however, and must be regulated from time to time. Even in the hands

machine

is

of a careful
in

workman

there will be considerable variation

the temperature at which the milk or cream is pasThis difficulty may be overcome and all the advanteurized.
tages of rapid heating and continuous operation retained by holding the milk or cream for a short time before cooling.

42

ICE The
Retarder.

CREAMS AND

ICES

At

the rate cream passes through a con-

a temperature of 140° F. to 145° To permit the use of a F. would accomphsh nothing. lower temperature in operating a continuous pasteurizer
tinuous
pasteurizer,

and
is

to secure greater efficiency, a device
in

known

as a retarder

used

connection with the pasteurizer.
is

The purpose
from

of the retarder

to retard or delay the flow of cream

Fig.

17.

A

Retarder.

the pasteurizer to the cooler.

By

this process the

cream

may be

held for any desired length of time at the pasteuriz-

ing temperature without any intermission in the flow of

cream, and a more thorough pasteurization
out the attendant
tures.
ills

is

secured with-

of pasteurization at higher tempera-

In other words, the use of a retarder combines the advantages of the continuous and the intermittent methods

of pasteurization.

The

intermittent process.

The milk or cream

is

heated

CARE OF MILK AXD CREAM AT FACTORY
to 140° F. or 150° F. in a large vat

43

and held at that temperature for the desired length of time, usually 20 to 30 minutes.
It is

claimed that this insures a more thorough pasteurizais

tion because the temperature

applied for a definite length

of time and

is

uniform throughout the mass.

Another ad-

Fig. 18.

Progress Holding Machine.

vantage claimed for this system is that the pasteurization is accomplished at a lower temperature, which does not impart a cooked flavor or otherwise afifect the properties of milk or cream to the same extent as the continuous method where
high temperatures are employed. The objections raised against this system are that larger machines are required in

44

ICE

CREAMS AND

ICES
it

handling the large batches of milk and cream, and

is

slower because of the intermittent action.

Fig.

ig.

Universal Vat

Pasteurizer.

Fig.

20.

Wizard

Pasteurizer.

After the milk or cream has been heated to the proper
point for the desired length of time
it

should be cooled a§

CARE OF MILK AND CREAM AT FACTORY
quickly and thoroughly as possible.

45

This is accomplished by running the milk or cream over a cooler having a double water-way. In these coolers the coils are in two sections, the upper one being cooled with ordinary water, and the

lower one cooled with ice water or cold brine. By means of such a cooler the pasteurized cream or milk may be reduced to a very low temperature. Cooling should be done as quickly and thoroughly as possible to prevent the germination of spores which have not been destroyed by heat. The pasteurized cream should
then be placed in the cream storage room and held at a

temperature of about 33" F. to 34° F. for 36 to 48 hours before it is used. In case the plant is not equipped with
cold storage
facilities,

the cans of pasteurized cream should
salt.

be placed in a tank and packed in a mixture of ice and

uniform cooling of the cream. Pasteurized cream that has been cooled and held in this way will keep better and the ice cream made from it will have a good body and a smooth texture.
Frequent stirring
will hasten the

Effects of pasteurization
ice cream.

upon the body and swell

of

Pasteurization partially destroys the viscosity

of the cream but this viscosity can be regained to some ex-

by holding the cream for some time at a low temperaIf the cream is not handled in this way, the ice cream made from it will not swell properly and will have a rather weak body. The success attained in using pasteurized cream will, therefore, depend upon the proper care of the cream
tent
ture.

after pasteurization.

Storage.
it

As soon

as the cream has gone over the cooler

should be transferred to a refrigerated storage room. The cans should be kept covered to protect the cream from

exposure to the

air,

Owing

to the fact that the cooling

46

ICE

CREAMS AND
very
little

ICES
low

rooms must be kept
temperature, there
dition should be

tightly closed in order to maintain a

is

change of

air

;

consequently,

the rooms will in time become foul and musty.

Such a conguarded against and an effort made to keep the cream storage rooms sweet and clean and the air dry. A temperature very near the freezing point should be maintained at
all

times.
is

and if the temperagrowth of bacteria, the number of bacteria in the milk and cream will increase quite rapidly from the spores which were not destroyed in pasteurization. There are, therefore, two reasons for holding the cream and milk at a low temperature namely, to restore viscosity and to prevent the growth of bacteria. The sweet cream in the storage rooms must not be allowed to freeze, however, because there is a tendency for the cream to become buttery when it is again melted. The advantages of pasteurization are a slight improvement in the body and texture of the ice cream, provided of course, that the cream is properly aged before being used, and a reduction in the number of bacteria in the ice cream. The disadvantages are an increase in manufacturing costs, due to the extra machinery needed and extra time required, and more fuel consumed. There is also the liability of producing a weak bodied ice cream and of obtaining a smaller yield, unless there are good facilities for cooling and storing the cream. Another quite important point is
not
sterile,

Pasteurized cream
is

ture

at all favorable for the

;

the fact that the lactic acid bacteria are destroyed
quently, if the temperature in the storage

;

conse-

room should hap-

pen

to

go up, the bacteria that develop in the cream will

be of the more undesirable type.

"

CARE OF MILK AND CREAM AT FACTORY
The
cost of pasteurization
-

47
over

is

estimated at a
little

little

0.3 of a cent a gallon for milk

and a

over 0.6 of a cent

The tests conducted by the U. S. Department of Agriculture also show that the " flash heat process is more expensive than the " holder " or intermita gallon for cream.
tent process.

The

cost of pasteurization

may

in

many

cases

be

still

further reduced by utilizing the heat contained in the

exhaust steam from the engine.
ficient, in

many
it

cases, for all the pasteurizing
utilized instead

This heat would be sufdone in the
of being per-

plant,

if

were properly

mitted to go to waste.
2

Office of Information, U. S.

Department of Agriculture.

CHAPTER

IV

CONDENSED MILK, MILK POWDER^ AND HOilOGENIZED CREAM
Condensed milk and milk powder are very frequently used cream mixture, where they serve the double purpose of making up a part of the batch and have a stabilizing effect as well. Because of the high percentage of milk solids which they contain, their chief value in ice cream making, aside from their food value, is in giving better body and texture to the frozen product. In the manufacture of condensed milk and milk powder, the water or a large part
in the ice

of

it

is

driven

off,

leaving the solids in a highly concen-

trated form.

Because of this high concentration it is very important that the milk used in the manufacture of these
substances be of good quality.

The

quality of the milk used in the manufacture of con-

densed milk must be of the best obtainable.
densers learned, early in their experience, that

The conwhen the

milk

is

brought into a concentrated form, the acids that

developed, and any undesirable odors or contaminations

which the milk may contain are also concentrated. To make good condensed milk it is necessary first of all to secure a supply of milk that is pure, fresh, and as free from contamination as possible. The process of condensing this milk consists in remo\'ing from it a considerable portion of the water by evaporation. According to the pure food

CONDENSED MILK, MILK POWDER

49

standard, " Condensed milk, evaporated milk, is milk from which a considerable portion of water has been evaporated and which contains not less than 28 per cent, of milk solids of which not less than 27.5 per cent, is milk fat." ^

contained in the milk

process of evaporating and condensing the water is accomplished by heating it under reduced pressure. The purpose of evaporating under re-

The

duced pressure is to .avoid giving the milk a cooked flavor and also to avoid, as far as possible, all those changes ordinarily brought about in milk by high heating. Since the
boiling point of milk
it

little higher than that of water, condense the milk at that temperature without caramelizing part of the sugar and imparting is

a

would be impossible

to

a pronounced cooked flavor to the finished product.

To

avoid these and other changes in the milk
essary to condense
it

it

becomes necSince the
it

at a

lower temperature.

boiling point varies with the atmospheric pressure,
possible to bring milk to a boil at a temperature of
F. to

is

130°

135° F. by reducing the pressure.
this

used for
coil

purpose

is is

known

as a

The apparatus vacuum pan.
The

The vacuum pan

a large kettle containing a steam

or steam jacket to supply the necessary heat.
is

pressure within the pan

pump

reduced by means of a vacuum and a 26-inch vacuum maintained until the milk has

conditions the water

reached the proper degree of concentration. Under these is evaporated quite rapidly and passes
into the condenser in the

form of vapor.

The condenser

is

located at the top of the

vacuum pan

and is directly connected with it. As the milk boils the vapor rises and passes out of the vacuum pan into the condenser, which is simply a horizontal extension of the vacuum
1

Bulletin 143, Indiana station, page 484.

so

ICE

CREAMS AND

ICES

Fig. 21.

Vacuum Pan

in the

Elkhorn

\'alley

Condensory.

CONDENSED MILK, MILK POWDER
pan.
a spray of cold water which causes
it

51

In the condenser the vapor conies into contact with
to condense.

The

con-

densed vapor and the condensing water are carried off by means of a pump. This process goes on until the milk is
concentrated to the proper density.
process
is

From

this point the

somewhat

different for

canned condensed milk

and the condensed bulk milk. Condensed bulk milk. The condensed milk used in ice cream making is made in much the same way, except that The it is not usually put up in cans and is not sterilized. first part of the process is the same. When condensed to the desired point, the steam is shut off and the vacuum broken but the milk is allowed to stand in the pan, receiving the heat only from the jacket or by blowing steam directly into the milk in the pan. This is called super-heating and is prevent precipitation .of the sugar. In the done to the super-heating the milk becomes very thick and heavy. It is then drawn and cooled as quickly as possible and put up
in ordinary milk cans.

The

sterilizing is omitted

because

the milk

is

intended for immediate use and should not be
It is

held for any length of time.
ice

used quite extensively in

cream making both as a part of the batch and as a means of improving the body of the ice cream. Its effect upon the body of ice cream is due to the high percentage of milk solids which it contains. Milk powder is also used as a stabilizer and as a part of
the batch.
It consists of

the solids of milk reduced to a

dry state by evaporation of the moisture contained in the milk. Milk powder is a comparatively recent product but has been steadily growing in favor on account of its convenient form and the various uses to which it may be put.
It is

used in various ways in the manufacture of

ice

cream.

52

ICE

CREAMS AND ICES

The manufacture

of milk powder, therefore, bears quite

an important relation to the ice cream industry, particularly in those localities where an abundant supply of raw milk

and cream

is

difficult to obtain.
is

The

process of manufacit

turing milk powder
thought, seem.

not as simple as

might, at

first

The same precautions that must be observed in selecting milk for the manufacture of condensed milk apply also to milk that is to be used in the manufacture of milk powder.
milk,

Whole fresh and of good quality. skim milk, or partly skim milk may be used. The problem of eliminating all of the water from this milk,
The milk used must be
simple as
it

may

seem, was solved only after

much

experi-

mentation and repeated failures.
In the manufacturing process the milk must be reduced
to a dry

powder which

is

easily soluble in
all

water and

will

give a solution possessing
milk.
field

of the properties of normal

The problem which confronted
was
to discover a process

the i)ioneers in this
re-

by which milk could be

duced to a powdered form without breaking down some of the complex constituents of milk or rendering them insoluThe methods now employed may for convenience be ble. divided into two general groups." One may be termed the atomiz'uiij process and the other the hot cylinder or roller process. A partial vacuum is also sometimes employed in either of these processes to reduce the temperature at which
complete evaporation takes place.

In the atomizing process the milk is and then condensed in a vacuum pan.
milk
is

first

pasteurized

The condensed
The

forced through an atomizer into a chamber through
filtered air are circulated.

which heated currents of
2

F. B.

Fulmer

in Butter^

Cheese

&

Egg

Journal, April

i6, 1913.

CONDENSED MILK, MILK POWDER
milk being
is

S3

in the

form of a very
it

fine spray, loses its

mois-

ture almost as soon as
floor in the

enters the chamber.

The vapor

carried off by the air currents and the solids fall to the

form of powder. In the hot cylinder process the milk is sprayed continuously upon a hot cylinder which revolves at a slow The water evaporates very quickly and is carried speed. off by means of a ventilator. The milk solids are deposited upon the polished surface of the cylinder and are removed as fast as deposited by

means of stripping knives. One hundred pounds of skim milk are
reduced to about Syi or 9 pounds of milk powder.
This powder
Its
is

sometimes used in
is

the ice cream industry as a stabilizer.

value as a stabilizer
it

due

to the

fact that

increases the per cent,

of milk solids in the ice cream mix-

ture giving the ice cream a some-

what
iy!>

better

body.

One-half

to

pounds of milk powder may be

The in a five-gallon batch. powder should be mixed with sugar and then added to the cream. The milk solids in the milk powder increase the density of the mix and
used
give a better texture and flavor to

the ice cream.

Its

greatest

value,

Hauk's Emulser.

however,

is

in

supplementing

the

cream supply by a process known as homogenization. The objects of homogenizing normal milk and cream,

54

ICE CREAlVrS
to be

AND

ICES

which are
readily

used

to obtain a mixture

in the manufacture of ice cream, are from which the fat will not separate

and

to increase the viscosity of the cream.

Owing
less

to the fact that the fat globules are split

up

into

more minute
is

globules, there

dan-

ger of the mixture churning

when

it

is

agitated in

the freezer.

Natural cream

which has been passed through the homogenizer is much more viscous than untreated cream of the
richness.

same
in

When

used

the ice cream mixture, the
effect of this increased vis-

cosity is an increased swell

and a better body and texture in the ice cream.

The

homogenizer will also aid in solving the problem of obFig. 23.

The DeLaval
Emulser.

Centrifugal taining a sufficient
^
,

amount

of cream, because a mixture

of milk powder, water, and unsalted butter when passed through the machine gives a cream of good quality which may be used to supplement the regular cream supply.

homogenization. In making homoof skim milk and unsalted butter or a mixture of milk powder, water, and unsalted butter is heated to a temperature of 150° F. or 160° F. At this temperature the fat is in a liquid condition which is very necessary to successful homogenization. This emulsion of fat and skim milk is then forced through
process
cream,
of

The

genized

a

mixture

CONDENSED MILK, MILK POWDER
a very small aperture.
split

55

In this process the fat globules are

up and mixed with the skim milk in a perfectly homogenous condition. The cream thus obtained is much

more viscous than ordinary cream of the same
is

richness and therefore of particular value for ice cream making.^

From

the foregoing brief discussion

it

is

evident that

there are several reasons for using condensed milk, milk

Fig.

24.

The Cooksley Creamer.

powder, and homogenized cream in the manufacture of ice cream. In the first place, the food value, body, and texture of the ice cream are greatly improved by the use of any of these substances or a mixture of them. The improvement in body where condensed milk or milk powder is used is due largely to the increase in milk solids which increases the
viscosity of the ice

cream mixture.

creased viscosity

it is

properly in freezing.
3

As a result of the inmuch easier to get the cream to swell The milk solids other than fat which
see

For a more

detailed discussion of homogenizing machines

Chapter XVII.

56

ICE

CREAMS AND

ICES

these substances contain, modify the natural cream flavor to

some

extent, giving the ice

ing flavor.

These

solids also

should not be overlooked.

cream a somewhat more pleashave a high food value which The proportions in which these
is

and other ingredients should be used

discussed in an-

Fig. 25.

The Gaulin Homogenizer.

it may be well to point out here that a combination of homogenized cream and condensed milk

Other chapter, but

may

give too heavy a body.

avoided and
in the

may

easily

This condition should be be overcome by altering the pro-

portion of homogenized cream and condensed milk used

mixture.

CONDENSED MILK, MILK POWDER
:

57

This brief synopsis of the manufacturing process for conNote densed milk and milk powder is given here in order that ice cream makers may have some idea of the nature of these substances and their function in the ice cream mixture. Those who are interested in the manufactvire of these substances will find more detailed information in a new book entitled " Condensed Milk and Milk Powder," recentlv published by Prof. O. F. Hunziker,

CHAPTER V
STABILIZERS
Stabilizers
^

are substances added to ice cream for the purcrystals in

pose of improving the body and texture of the ice cream

by preventing the formation of
ished product.

ice

the
is

fin-

added to give the ice cream a better body is termed a binder, and a substance added to give a smooth texture and prevent the formation of ice crystals is termed a filler. As a matter
of fact a substance that will act as a binder will act as a

In some cases a substance which

These terms, however, are somewhat mislead" stabilizer " comes nearer suggesting the true function of these substances in ice cream. Body and texture are so intimately related that the two usually go together and in many places these terms are used interchangeably. On this point Washburn says,^ " The words body and texture are used in ice cream making to mean two quite different things. Body is synonymous with structure It refers to the entire mass as a unit. or substance. Texture, on the other hand, has to do with the finer make-up of the article. The one has to do with the mass characteristics the other with the arrangement of the particles." There are numerous substances which may be used as
filler

also.

ing.

The term

.

.

.

;

1

Sometimes referred
Bulletin 155,

to as " holders,'' " colloids,'' " binders,"

and

"

fillers."
2

Vermont

station.

S8

STABILIZERS

/
'

59

stabilizers. The most common ones are starch, egg albumen, milk solids, gums, gelatin, and prepared powders made from a mixture of two or more of these. The starchy stabilizers are still used quite extensively in ice cream making. Corn starch, wheat flour, rice flour, and arrow starch are the most common of these. Rice flour meets with considerable favor on account of the small

size of the starch grains.

All starchy substances, however,

should be cooked before being used in ice cream because

down in the cooking process and are more evenly and thoroughly incorporated with the cream.
the starch grains break
If the starch
is

not cooked the coarse grains will very likely

be apparent in the finished product.
ers are

sometimes used

cheaper grades. mixtures containing eggs. Eggs, when used in ice cream, act both as a stabilizer and as a flavor. Ice cream which contains many eggs has a very smooth texture, a heavy body, and a pronounced custard flavor.
Ice cream mixtures of this class

These starchy stabilizcream and in the They are rarely used in the fancy cooked
in the plain ice

must always

be cooked before the mixture is frozen. Milk solids, however, do not require cooking and serve

a double purpose in the ice cream mixture. These substances are added to the mixture either as milk powder, condensed milk, or in the form of homogenized cream. Where
these substances are used in the mixture the ice cream has

a better body and texture and also a higher food value on account of the higher percentage of milk soHds which it
contains.

In addition to the substances already mentioned,

there are certain

gums which
the

are sometimes used in ice

cream,

Indian

gum

is

name given

to a class of

gums which

6o

ICE

CREAMS AND ICES
According
to

are nearly alike in origin and composition.

Circular 94 of the Bureau of Chemistry, " it appears reasonably certain that two gums at least are justly characterized by this term
. . .

both of which find local application

as substitutes for tragacanth."

Tragacanth is the name of a gum obtained from plants found in the mountains of Asia Minor.^ The gum exudes through natural fissures and through incisions, appearing Indian gum, on the as ribbon and leaf or flake tragacanth. other hand, occurs as irregularly shaped lumps, so it is quite different in appearance. It is used in the powdered forms
to adulterate the

more expensive gum

tragacanth.

When
but

placed in water,
swells

gum

tragacanth does not dissolve,

and becomes so distended as to occupy all of the water in which it is placed, forming an adhesive, viscous mass. When used as a stabilizer for ice cream the required amount of gum is soaked in warm water before being added to the ice cream mixture, or a " gum tragacanth stock " may be prepared by placing one ounce of gum tragacanth in a quart of water and heating gently until the entire mass becomes thick and tenacious. About three pounds of sugar are then added and in this condition will
keen for
se\-eral

weeks.*

Gum
that
it

tragacanth possesses some advantages over
tasteless, odorless,

many

of the other substances used in the ice cream mixture in
is

satisfactory stabilizer
gelatin, particularly

and easy to use. It is a very and is frequently used in place of where public sentiment is against the
stabilizers.
fibrils

use of the gelatinoid
Gelatin
8 is

obtained from bones, cartilages, and

Circular 94, Bureau of Chemistry.

-Bulletin 15s,

Vermont

station.

STABILIZERS
of connective tissue.
It is

6i

extracted from these by boiling

with water and forms into a thick jelly-hke mass upon cooHng. Although gelatin is an albuminous substance, it
differs from other albumins in that it does not contain such proteid substances as tyrosine and tryptophane,^ and therefore is almost odorless and tasteless. When properly

used and in moderate amounts its presence cannot be detected by the odor or flavor of the ice cream. The use of gelatin in the ice cream mixture need not

maker any difficulty if care is taken to have the gelatin thoroughly melted before it is added to the cream. This is accomplished by melting it in hot water or in a part of the milk used in standardizing the cream. It must be remembered that gelatin is slightly acid. If it is melted in a small amount of milk, there may be enough
give the ice cream
acid present to cause the milk to curdle.

The

difficulty

may

be easily avoided by melting the gelatin in a larger quantity of milk. In some factories an ordinary steam kettle, such
as the kettle used for cooking Neapolitan ice cream, for melting gelatin. free
ice
is

used

When

the gelatin

is

all

melted and

from lumps it should be strained and stirred into the cream mixture. The advantages of gelatin as a stabilizer over some of
In the
first place,

the other substances are very apparent.
it is

more

effective in preventing the formation of ice crys-

cream containing gelatin will stand The texture of the ice cream is suIt should be perior to that obtained by the use of starches. pointed out, however, that nothing but pure, wholesome gelaIt is a false economy and dangerous tin should be used. practice to use the lower and cheaper grades of gelatin.
tals

and as a

result ice
better.

shipment much

5 "

Text Book of Physiological Chemistry.''

62

ICE

CREAMS AND

ICES

Prepared powders, known as ice cream powders or by some special trade name, are made up for the most part from some of the substances described above. The value of these substances depends upon the presence of finely powdered gum tragacanth or gelatin or a mixture of these in rice flour, powdered arrow root, and sugar. The results obtained from the use of these is sometimes quite satisfactory but on the whole it would seem more desirable for the ice cream maker to know the exact nature and composition of the stabilizer used. City ordinances and
in ice

uniform in regard to the use of stabilizers cream; hence, the importance of knowing the composition of prepared substances such as ice cream powders. The object of using stabilizers. It seems that the opinstate laws are not

ion quite

of ice cream

commonly held by those unfamiliar with the process making is that these stabilizers are adulterants.
is

This, however,

not the case, as these substances are
in cakes to give

almost analogous to the baking powders or cream of tartar

and soda, eggs, and other substances used
lightness.

In other words, stabilizers are essential to the

production of good body and texture in ice cream

made
of
is

under practical commercial conditions.
these have a high food value.
well

Instead of being

adulterants or substitutes for other food products,

many

The food value of eggs

which are added in the form of milk powder or condensed milk have a high food value also and at the same time improve the flavor of the
to
all.

known

The milk

solids

ice

cream.
effect of stabilizers

The

somewhat overestimated.
that a stabilizer
is

upon swell has apparently been The opinion held by some is
ice

used to increase the swell of the ice cream.

This opinion

is

shared by

many

cream makers

also, but,

STABILIZERS
according to
It
all

63

data on this subject available at the present

time, stabilizers apparently have just the opposite effect."

has been pointed out that as a rule where varying amounts
is

of these substances are used there

a very noticeable re-

duction in the average swell of the ice cream during the freezing process.

The use

of gelatin in ice cream
it

not only because some consider
of the fact that
it

may

is frequently denounced an adulterant but because become contaminated in the manuis

facturing process.
grades, great care
gelatin used in ice
tions

Since this

quite true of the lower

should be exercised in selecting the

cream making. When the proper precauhave been taken to select gelatin of known purity, there can be no reasonable grounds for objecting to its use in the ice cream mixture. The amount used is quite insignificant and instead of being a harmful substance,
it is

a food of

Although gelatin is not a tissue builder, it is said to have a heat and energy value about equal to that of proteids and is very easily digested. Owing to the fact that gelatin melts very readily in warm water and solidifies again upon cooling, it makes an excellent stabilizer for ice creams and sherbets. The use of stabilizers in ice creams and sherbets is a matter of considerable importance to the ice cream maker where the product must be shipped or hauled some distance before it reaches the consumer. In the hot summer weather it is difficult to ice a tub thoroughly enough so it will stand a very long shipment unless a stabilizer of some sort has been used. The temperature of the ice cream need rise only a few degrees to bring about a condition in which ice If the crystals will form when the ice cream is repacked.
little

no

value.

"

Bulletin 155,

Vermont

station.

;

64
ice

ICE

CREAMS AND

ICES

cream becomes even slightly softened in transit and is down and frozen, it will be found that the texture has become more or less granular. The difficulties in handling rail shipments of ice cream in hot weather must be encountered to be fully appreciated. These difficulties are overcome, in part at least, by the judicious use of stabilizers.
then iced
Just
in ice

how

a stabilizer prevents the formation of ice crystals
is

cream

not definitely known.

According

to

Washin this

burn, gelatin prevents the formation of sharp spines of ice

by forming a

film

around the small

ice crystals,
size.

and

way

prevents them from increasing in

He

also as-

serts that

gum

tragacanth does not form such a film or

capsule around the ice crystal but

when used

in connection
'^

with gelatin serves to hold the gelatin capsules together.

The

truth

of this theory remains to be demonstrated

nevertheless, these substances,
colloids,

which are sometimes

called

when

properly used, enhance the value of ice cream
giving a better body and finer texture which

considerably
will

b}'

not become granular after the ice cream stands for a
the formulas given in chapters and XI mentioned as a stabilizer. In these and other

time.

In nearly
gelatin only

all
is

X

formulas other stabilizers or a combination of them
substituted
7

may

be

if

so desired.
the National Association of Ice

Washburn before

Cream jManu-

facturers, Chicago,

October 1913.

CHAPTER VI
FL.WORING
Frozen desserts are valued mainly because of
being the case, the commercial value of
largely
ice

their pleas-

ing flavor and their cooling and refreshing effects.

This

cream depends

upon the care exercised

in selecting suitable flavor-

ing material and upon proper freezing rather than the food

value of the products.
material which
that
care.
it is

may

be used and so

There are so many kinds of flavoring many brands and grades

necessary to select flavoring substances with great

Spices, sugars, syrups, crushed fruits, fruit juices, extracts

and nuts are the flavoring substances used

in

one way

or another in the manufacture

of ice creams and ices.

Many
The

of these, such as the spices, find but occasional use

cream mixture. Cloves, nutmeg, ginger, cinnamon and coffee Some of these are used are the ones most frequently used. only to modify other flavors as in the case of cinnamon, which is often combined with chocolate. Coffee, however, is frequently used as the principal flavoring agent in ice cream and is a popular flavor with some people. Sugars and syrups serve both as sweetening and flavoring The most important flavoring substances of this agents. class are vanilla sugar, maple sugar and chocolate, maple and
in the ice

spices.

caramel syrups.
65

66

ICE
Vanilla sugar

CREAMS AND

ICES

is employed only in the manufacture of cercooked creams. The sugar is prepared by tain fancy and pulverizing ten ounces of sugar with an ounce of finely cut vanilla beans and then sifting the mixture to remove the

coarse pulp.

The seeds of the vanilla bean should be allowed through the sieve with the pulverized sugar. to pass Maple sugar is one source of maple flavor but is not used to the same extent as maple syrup or maple extract. Chocolate syrup may be prepared by boiling a pound
of bitter chocolate, a

pound of cocoa and four pounds of

sugar with enough water to give a thick syrup.
of this syrup
as a source of
is

One

quart

sufficient for ten gallons of ice
is

cream.

Maple syrup
to

used'

more frequently than maple sugar

This material is too well known need discussion here. Caramel syrup may be obtained ready prepared, or it may be made by melting one pound of refined sugar in a stew pan or frying pan over a moderate fire, gradually increasing the temperature to about 400° F. or until the

maple

flavor.

syrup has a very dark brown color and a bitter taste. it is in this condition, a pint of water should be added very slowly and boiled until the syrup is as thick as molasses. Care should be taken not to get the syrup too thick or

When

it will crystallize upon cooling. In that case more water must be added and the syrup boiled again. Fruit flavors may be obtained in the form of a syrup These syrups, however, are more for soda fountain also. purposes and are therefore little used in the ice cream mixture. Crushed fruits and fruit juices are more satisfactory

than the fruit syrups as flavoring for ice cream.

Crushed
cream,
ices,

fruits

and fruit juices. and sherbets the fresh

As

a flavoring for ice

fruit gives the

most

sat-

FLA\'ORING
isfactory results.
If

(^7

Only sound, mature
to

fruit

should be used.
obtain the best
it

fresh fruit cannot be obtained, canned and preserved

fruits

may be used

good advantage.

To

results in the use of canned, dried or preserved fruit

is

very important that fruit of good quality be selected, because the drying and preserving alters the natural fruit

somewhat.

This

is

particularly noticeable in the lower

and

cheaper grades of

fruit.

The

fruit flavors

most frequently

called for are orange,

lemon, raspberry, apricot, cherry, pineapple and strawberry.

Orange and lemon

flavor

may
in

be obtained in the form of an
finest quality of ice

extract, but for ices

and

making the

cream, the flavor should be obtained directly from the fruit. Orange. Owing to its pleasant, mildly acid flavor, orange
juice as
it

is

used

in a great

many formulas
it is

for ices

and

sherbets,

blends nicely with almost any fruit flavor.

In preparing
ice,

the orange juice, unless

used in orange sherbet or
into the juice.

the fruit must be peeled to prevent any of the essential

oil

which
in

is

in the rind

from getting

Lemon
water
juice

flavor

is

not used so extensively in ice cream as

In the ice cream trade both the and the extract are employed. The fruit juice is used not only to produce a lemon flavor but to supply the desired fruit acid and to modify the flavor of other fruits. I'he best lemons to select are the large, smooth ones with
ices

and

sherbets.

thin rinds.

They should be

stored in a cool, dry place until

used.

A

very fine lemon flavor
In
fact, in

may

be obtained by grating

the outer part of the rinds of several lemons and mixing with

the sugar.
is

many

added

solely to increase the acidity, the

formulas where lemon juice lemons must be
into the mixture, as
will

carefully pared before being squeezed to prevent any of the essential oil

from getting

it

68

ICE

CREAMS AND ICES
when
it is

impart a distinct lemon flavor

not desired.

The

inner white rind as well as the outer rind must be removed

and the lemons cut in halves and
before the fruit
is

all

the seeds removed

pressed.

Strain the juice before using.

The other

fruit flavors, except pineapple

and strawberry,

are less frequently used.

Many

of these are most popular

when
flavor
flculty
ice

the fresh fruits are in season.
is

Since the desired

easUy obtained from the fresh fruit no great difis encountered in supplying the demand for fruit

creams. Canned or preserved fruits, however, may be used with very satisfactory results, especially for the pineapple and strawberry ice creams.

Pineapple flavor.

It is

impossible to prepare an extract

of pineapple from the fruit; hence, the extracts of that flavor
are always synthetic products.

The

flavor of this

fruit,

pronounced that a good pineapple flavor may be imparted to ice creams and ices from the fruit alone and without the addition of extracts. If fresh fruits
however,
is

sufficiently

are used, care should be taken to select mature, well-ripened
fruit.

The

fruit should be
is

pared and the cores removed bestrained.

fore the pulp

mashed and

Only

as

much

fruit as

can be used at once should be prepared at a time.
pineapples
in ice

Canned

may be

obtained from any supply house dealing

cream

flavors

and

supplies.

The high grade canned
results as

fruit is of excellent flavor

a flavoring for ice

and gives very good creams and ices.
This flavor,

Strawberry

flavor.

like the pineapple,

is

best

obtained by using the fruit.

Select well ripened fruit of

good
ries.

color.

Clean them carefully and discard all poor berThey should then be crushed and strained through

a fine wire strainer.

Add

a

little

sugar to the crushed fruit
fruit is

and mix thoroughly.

Even when fresh

used

it

is

FLAVORING

69

sometimes desirable to add a small quantity of good strawberry extract to bring out the flavor and enough fruit red
color to give a light pink color to the cream.

Many

factories put

up

their

own

strawberries during the

season of the year
sugar.

when

berries are cheap.

The
if

berries

are cleaned, crushed, and mixed with an equal part of cane

The

fruit thus prepared will

keep well

stored in

a cool place.

If the factory does not
it

room

for supplies of this kind,

will
is

have a cold storage be necessary to pas-

teurize the fruit after the sugar

added.

usually stored in barrels until needed.

The fruit is The Havor of the

strawberries prepared in this
the fresh fruit.

way

is

nearly equal to that of

When

fresh strawberries can not be 'obtained
fruits.

it

will

be

necessary to use preserved

In such Cases an extract

should also be used to bring out a good strawberry flavor.

Lemon

juice should also be Used to increase the acidity

and
and

give a fresh fruit flavor.

Other

fruit flavors such as raspberry, peach, apricot
it

cherry are very mild and

may

be necessary to strengthen

the flavor by using an artificial flavoring substance.

When

canned

fruit is used,

fruit acid

must be supplied by the
flavors that cannot be
artificial

addition of lemon juice.

Fruit extracts.
products.
artificial

There are some

obtained in extract form except as

or synthetic

Most
flavors
is

fruit flavors belong to this class.

These
genuine

correspond very
in

nearly to the

flavor

which

most cases due

to a class of chemical

bodies

known

as esters or ethers,^ which are produced in

the growth of the plant.

These same substances may be

obtained from other sources, such as the higher alcohols,
1 "

Year Book of U.

S.

Department of Agriculture,

igo8."

70

ICE
in

CREAMS AND

ICES

and are used
flavors.

the production of synthetic or artificial

The

synthetic flavors are usually colored with coal

tar products and, according to the Federal and some State laws, must be labeled " Imitation " or " Artificial."

The
others,

the most important of the extract flavors.

Lemon, orange and vanilla are There are some however, such as mint, wintergreen and certain nut
extract
flavors.

Fig. 26.

Expressing lemon

oil, Mascali, Sicily. of Agriculture.)

(U. S. Department

flavors

which are sometimes used
a flavoring extract "

in

extract form.

Acethyl

cording to the standards adopted by the Department of
Agriculture,
is

a

solution,

in

alcohol of proper strength, of the sapid and odorous principles derived

with or without

from an aromatic plant or parts of the plant, its coloring matter, and conforms in name
its

to the plant used in

preparation."

This definition at

FLA\'ORING
once excludes
all

71

preparations which are not solutions in

alcohol and eliminates the various forms of prepared flavored

sugars used abroad.

orange extracts are used only to a very limmanufacture of ice creams, largely because the flavor is easily obtained from the fresh fruit. These extracts are made from the essential oil derived from the
ited extent in the

Lemon and

rind of the fruit.

High grade
strong alcohol.

extracts are

made by

dissolving this
is filtered

oil
is

in

alcohol is the most costly constituent ready for use. of such an extract because it requires a very strong alcohol
to hold five per cent, of the oil in solution.

The The

alcoholic solution

and

then

Low
oil

grade extracts are made by repeatedly shaking the

with dilute alcohol. These extracts have the odor of the higher extracts but the flavor will cook or freeze out
quite easily.
Citronella

and lemon grass

citral

are some-

times used to strengthen the flavor, and glycerin, sugar, and other substances are added to improve the body of these

cheaper extracts.^

orange extract

Terpenless extract. The cost of producing lemon or may be reduced considerably by producing This is accomplished by making a soluterpenless extract. tion of the oil in alcohol and then diluting the solution. The oil separates out and may be removed. Another method is to wash the lemon or orange oil with dilute alcoBy either of these methods the citral, which is the hol. principal flavoring substance of the oil, is removed, the

terpenes remaining undissolved.
as the principal flavoring agent or to modify
?

Peppermint and wintergreen are sometimes used either some other
"

Year Book of U.

S.

Department of Agriculture,

1908,"

72

ICE

CREAMS AND ICES

FLAVORING
flavor.
is

73
the essential oil which
distillation.

These

flavors are

made from

obtained directly from the plant by

The nut
is

flavors

may

be obtained

in extract

form.

There

a limited

demand

for certain of these extracts in the

manu-

facture of ice creams.
pistachio

The most important nut

extracts are

and almond.
extract
is

Almond
flavors

useful in the manufacture of ice cream

either as the principal flavor or to strengthen natural nut

and to blend with other flavoring substances. It is prepared by making a solution of oil of bitter almonds in strong alcohol. In order to comply with the food standards this extract must contain not less than one per cent, of the
flavoring material.

source of almond

oil,

Seeds of apricots are the principal although considerable quantities are

obtained from almonds and peach kernels.
these various sources are
as
oil all

The

oils

from

very similar and are known
oil

of bitter almonds.

In preparing

of bitter almonds

the kernels are ground and pressed by hydraulic pressure to
free

them from the
is

fatty oils

which they contain.
finally

The

residue

then reground, fermented and

distilled

with steam.
acid,

The
is

resulting product contains hydrocyanic

very poisonous and must be removed before the product can be used in the manufacture of extract. The distillate is treated with lime and copperas, which re-

which

agents remove the last traces of impurity. Artificial extracts are made from synthetic benzaldehyde, a coal tar product.'

Nut

flavors are not obtained exclusively

from

extracts,

however, the nuts themselves being used quite extensively
in combination with

some flavoring

extract.

Selecting and

preparing nuts.

Considerable care must

be exercised in selecting and preparing the nuts to be used
3 "

Year Book of U.

S.

Department of Agriculture,

1908,"

74
in ice

ICE

CREAMS AND
many

ICES

cream making.

Nothing but sound, non-rancid nuts
cases these

should be used and in
nuts.

may

require special

treatment such as roasting or boiling, as in the case of chest-

Nut

flavors

may sometimes

be obtained from some

preparation containing the nut as in the case of peanut butter.

almonds and filberts should have removed before being used in ice cream. This is known as blanching. In blanching nuts, first throw the shelled nuts into boiling water and let them remain there until the outer skin is easily removed by rubbing them between the finger and thumb. The nuts will have to remain in the boiling water for about one minute before the
Pistachios,

Blanching.

the dark outer skin

skins can be easily removed.

and thrown
ately.

into cold

They should then be drained water and the skins removed immedi-

Vanilla
of
all.

is

without an exception the most popular flavor
is

This flavor

usually obtained in extract form, but
is

a preparation of vanilla and sugar
certain cooked creams.

sometimes used

in

The
first

source of the flavor
is

is

the bean or seed pod of a
it

plant which

indigenous to southern Mexico where

was

used by the nati\es to flavor cocoa. The plant has since been introduced into other tropical countries where it
is

now

cultivated quite extensively, but in no case does the

transplanted bean develop the fine flavor of the Mexican
bean.

Cultivation.*
close

The
the

flowers,

which open

in the night

and

early

in

day,

are usually pollenated by hand.

Originally natural pollenization by insects

was depended

upon
t "

entirely, but,

owing
S.

to the irregularity of the crop, the
igo8,"

Year Pook of U,

Department of Agriculture,

FLAVORING
hand pollenization has

75

practically superseded the old method.

The

and is similar to the methods employed in plant breeding. A small amount of pollen is removed from the male blossoms and transferred to the female blossoms by means of a small splinter of wood. In
operation
is

quite simple

Fig. 28.

Mexican, Bourbon, and Tahiti vanilla bean.
partment of Agriculture.)

(U.

S.

De-

this

way

the

number of pods each vine

is

to

mature

is

easily
It

regulated according to the size and strength of the plant.
requires about six

pods to grow to

months from the flowering period for the that state of maturity in which they are in

the best condition for curing.

76
Curing.

ICE

CREAMS AND

ICES

are not allowed to dry upon the vine and aroma developed in this way is very inferior to the aroma and flavor developed in pods that have been picked at the proper stage and then cured. Considerable
as the flavor

The pods

experience

is

required to determine the proper stage of
If the

maturity in the pods.
the pods are

pods are picked too green, the

best flavor will not be developed in the curing process and

more

likely to

mold when put
is

into storage.

On

the other hand, an over-ripe pod
sell at

likely to split while

curing and will therefore

a lower price.

The aroma and

flavor are developed in the pods during

the curing process, the pods having neither an agreeable

odor nor flavor when
that the

first

gathered.

It is

claimed by some

due to a change brought about simply by drying, while others claim that it is due to a fermentation which takes place in the bean. The exact nature of the change which brings out the flavor of the bean is not well understood, but there are numerous methods by which the desired results may be attained. The most common and simplest method is to allow the pods to lie in the sun for several hours until thoroughly heated. They are then wrapped in blankets and
flavor developed in curing is

aroma and

the following day. These operations of heating and storage are repeated for several days. Sometimes the pods are treated with a special preparation of vegetable oil to promote the sweating which takes place while the beans are wrapped in blankets. Various other devices, such as manipulation by hand or by subjecting to a scalding bath
left until

are resorted

to, in

order to develop the desired flavor.

A

more uniform
has in

article is

produced by

artificial

drying which

many

places superseded the old sun drying method.

Grading.

The cured pods

are graded according to lengths

FLAVORING

11

and all split or otherwise defective pods removed. The former are sold as " splits " and the latter after being trimmed are sold as " cuts," both of which bring a lower After the pods have been stored price than the whole bean. for a time they become covered with a white coating of Although the Mexican beans are genervanillin crystals.

^^^^I^R''~

78
water.

ICE

CREAMS AND

ICES

After a few days the alcoholic solution, carrying
is

the flavor which has been dissolved out of the beans,

poured off and is then ready for use. Some manufacturers, however, make it a practice to age the extract for months
in large casks.

grade extracts are made from lower grade beans used in their preparation. As a result the body and flavor of the extract is not so good. Small quantities of essential oils are sometimes added to improve the flavor, and glycerin or sugar is added to improve the

Low

and

less alcohol is

body.
Artificial vanilla
artificial vanillin,
is

made

of various products, such as

cumarin and extract of tonka. Prune juice, caramel coloring, sugar, glycerin and other substances are employed to modify the flavor and give the
artificial

desired body.

The

flavor of these extracts

is

very pro-

nounced but lacks the fine qualities of the genuine product. Federal and some State laws require that such products be
labeled " Artificial " or " Imitation."

CHAPTER

VII

STANDARDIZING THE ICE CREAM MIXTURE
Standardizing is a means of altering the test of milk or cream by the addition of other milk, cream, or skim milk in such proportions that the mixture will contain a certain per cent, of butter fat.

Standardizing the cream to be used in the ice cream

mixture

is

of

considerable importance because

in

most

places the pure food laws require a certain per cent, of fat
in the ice cream.

The per

cent, of fat in the

mixture must

be varied according to the kind of ice cream to be made. It is only by accurate standardization that a uniform product

can be secured from day to day. The butter fat standard. The amount of butter fat ice cream must contain in order to comply with the pure food
is not the same in all States. The United States Pure Food Law defines ice cream as " a frozen product made from cream and sugar, with or without a natural flavoring, and containing not less than 14 per cent, of milk " Fruit ice cream is a frozen product made from fat." cream, sugar and sound, clean, mature fruits, and containing not less than 12 per cent, of milk fat." " Nut ice cream is a product made from cream, sugar and sound, non-rancid nuts, and containing not less than 12 per cent, of milk fat." Some States have no fat standard at all and in other States

standards

the standard

is

as high as 14 per cent.
effect,

Where
is

these high

standards are in

standardization
79

especially impor-

8o
tant.

ICE
The high

CREAMS AND

ICES
little

standards admit of but very
to be

variation

in the various

formulas for ice cream, but where special and
is

fancy ice cream
in

made

the richness of the cream will,

have to be varied to produce the desired results. It is only by careful standardization of the mixture that uniform results can be obtained. The standardizing of milk and cream should be based upon actual tests. The practice of mixing milk and cream in certain proportions without any regard to the test of either, will not produce a uniform grade of ice cream. Uniformity is of great importance in securing and holding trade and in preventing leaks and losses. There are several methods of standardizing which are very satisfactory. To find the proportions of milk and cream to use either of the following methods may be eminstances,

many

ployed.

Draw
left

a

rectangle with

hand corner place the

ardized.

At

the lower left

two diagonals. At the upper cream to be standhand corner place the test of the
test of the

milk to be used in standardizing.
rectangle place the desired
test.

In the center of the
the right hand corners
at the left

At

place the differences between the

numbers

hand

corner and the number in the center.

upper right hand corner represents the cream of the richness indicated by the left hand corner. The number at the lower right hand corner indicates the number of pounds of milk of the richness indicated by the number at the lower left hand corner. By mixing milk and cream in these proportions the desired test will be obtained. For example, if 35 per cent, cream is to
be standardized to 20 per cent, using 4 per cent, milk proceed as follows:

The number at the number of pounds of number at the upper

:

STANDARDIZING ICE CREAM MIXTURE

8i

Sixteen, which

is

the difference between 4 and 20, represents

the pounds of 35 per cent, cream that must be mixed with 15 pounds of 4 per cent, milk to make 31 pounds of 20

When the proportions of milk and cream have been found any amount of 35 per cent, cream may be standardized to 20 per cent, by mixing with 4 per cent, milk in the proportions of 16/31 of cream to 15/31 of
per cent, cream.
milk.
If

skim milk

is

used instead of whole milk the figures

would be

:

82

ICE

CREAMS AND

ICES

skim milk will

In this case a mixture composed of 20/35 cream and 15/35 test 20 per cent.

Another method of standardizing that
accurate and involves but
tiply the
little

is

quite simple and
:

Mulamount of cream by the difference between its test and the required test, and divide the product by the difference between the required test and the test of the milk to be added. Example: Standardize 120 pounds of 30 per cent, cream to 20 per cent., using 4.2 per cent. milk. 10, which is the difference between the test of 30 — 20 the cream and the required test. 20 — 4.2 15.8, which is the difference between the required test and the test of the milk to be added. Using these figures we have 120 X 10-^
figuring
is

as f ollov^^s

=

=

^75.95. Therefore, 75.95 pounds of 4.2 per cent, milk are required to reduce the test of 120 pounds
15.8 or
-^

^°"°

of 30 per cent, cream to 20 per cent.
this

The accuracy
3.1899
36.
lbs. lbs.
lbs. lbs.

of

method

is

shown by
lbs. lbs.

the following figures
fat

75.95
120.

4.2% milk contain

30% cream

contain

fat

Total 195.95

lbs.
^^s.

Total

39-1899

Therefore 195.95

20%

cream contain 39.19

fat.

Either of these methods will be found valuable as aids in
regulating the quality of the ice cream produced.

Standardizing the ice cream mixture. It is also very important that the ice cream maker should know how to calculate the per cent, of butter fat a given mixture will contain.
In addition to that
of ice cream.
it

is

necessary to

know

the

amount

of

butter fat in the mixture in order to find the cost of a gallon

In making these calculations

it

membered

that the sugar, flavoring, gelatin

must be and other

rein-

STANDARDIZING ICE CREAM MIXTURE
gradients

83

reduce

the

test

just

the

same

as

skim milk

would.

The

following example will

make

this clear.

20
4

lbs. lbs.

17% cream
sugar
flavoring
gelatin

2 oz. 2 oz.

2434

lbs.

of mixture

The 20 pounds of 17 per cent, cream contain 3.4 pounds of butter fat, which represents the total fat content of the ice
cream mixture.

To

determine the per cent, of fat in the

mixture, divide the pounds of butter fat by the total weight
of the mixture and point off

two places for per
butter
is
is

cent.

3.4-^24.25= 14.02%

fat.

In the following mixture the cream
of fat; but the method of procedure
12
lbs. lbs. lbs. lbs.

not the only source
the same.

24^

cream

4 4 4
24
12
lbs. lbs.
lbs.

condensed milk testing 8% fat whole milk testing 4% fat
sugar

2 oz. flavor
lbs.

2

oz.

of mixture
2.88
lbs.

24% cream

contain

fat
fat

4 4

8% 4%

condensed milk contain milk contain

.32 lbs.

.16 lbs. fat

3.36 lbs. fat in
the mixture

3.36-^24.125

= 13.93%

of fat in the mixture.

84

ICE
To
find

CREAMS AND

ICES

cream must be used to give a mixture of pounds of ice cream mixture mixture, divide the product by desired test of the by the of the cream and point off two places weight to be used, the
rich

how

a certain test, multiply the

for per cent.

Example

:

What

per cent, of butter fat must the cream

contain to give a mixture testing 9 per cent. ? Calculating on the basis of a mixture for ten gallons of
ice

Cream we would need 44 pounds of cream, eight pounds

of sugar, four ounces of flavor and four ounces of gelatin,

giving a total weight of 52j/< pounds.
52.5

X

-09

= 4-725

lbs.

of

fat.

Since none of the ingredients except the cream contain
butter fat, the entire 4.725 pounds will be contained in 44 pounds of cream; therefore, 4.725 10.74 9^, which

-^44^
the

represents the per cent, of butter fat which the cream must
contain.

The accuracy with which
fat.

work

is

carried out

should be checked up from time to time by testing the

mixture for

Testing for fat in ice cream by the Babcock method presents some difficulties owing to the presence of the sugar.

of procedure in preparing the ice cream vary more or less with the different kinds and cream. The ice cream maker sho'uld therefore

have a clearly defihed idea as to the results desired and then
results.

and put together such ingredients as will give these The various ingrg^lients should be weighed or measured very exactly, as it is only in this way that uniform
select

results can be obtained.

Selecting the cream

is

order to
that the

make

a high grade

one of the first considerations. In ice cream, it is very important

cream and milk used be of good quality. This from foreign odors and flavors, a sufficiently high per cent, of fat, and an acidity of not over The objections to foreign odors have already 0.25 per cent.
implies a freedom

been mentioned.^ It has been pointed out that there is but one way to look at such defects, and that is to consider

them very ob j ectionable.

The
the

acidity of the cream, however,

is

not always such a

serious defect.

In fact,

if

the fermentation taking place in

cream

is

purely of an acid nature and has developed to a
it is

point where

just noticeable to the taste, the excess acid

can be neutralized by the addition of viscogen or sodium
hydroxide, and an
'^

equal

amount of fresh sweet cream
86

See page

2.

-

PREPARING THE ICE CREAM MIXTURE
added.
of
fair

87

The mixture can then be used
quality.

in

making

ice

cream

This practice, although sometimes followed, is not to be recommended, because of the fact that a partly soured cream contains enormous numbers of lactic
acid bacteria.
acidity
is less

It is

mentioned here to show that a

slight

objectionable than other taints and defects in

the cream.

it

The richness of the cream is such a variable factor that can be discussed here only in very general terms. In the
there are pure food laws in most States which

first place,

regulate the

amount of butter

fat

which the

ice

cream must

contain; consequently, the fat content of the cream must

be sufficiently high so that when sugar, flavoring, and other
ingredients have been added, the mixture will contain sufficient butter fat to satisfy the

Since butter fat
of the ice

pure food authorities. one of the most expensive constituents cream, the price for which the product must sell
is

should be carefully considered. The keen business man, however, will take the popular demand as the safest criterion upon which to base the amount of butter fat to put into
the ice cream mixture.

The sugar
demand
is

is

also a variable constituent.

the only guide as to the

the mixture should contain.
will require

The popular amount of sugar which Under average conditions it

about 15 or 16 per cent, of sugar to sweeter^

an

cream mixture which does not contain eggs, and somewhat more for sherbets and for ice creams containing
ice

eggs.

The kind of sugar used in bets may be either granulated
In some
2

ordinary ice creams and sherbeet or granulated cane sugar.

formulas, however, better results are obtained by

Bulletin 136,

Maryland

station.

(See page 268.)

ICK CREyVMS
using some puh'crizcd
eggs beaten to a froth.
suyiir.

AND
This
;

ICES
l^iiul

of sugar

is

also

preferable fur making nicriiii;uc

i.

c, the sweelened white of

Preparation of the sugar.

In most eases the sugar will

need

little

or

no preparation

before

being

used.

(

are

must always be
of the sugar

tal<en,

however, to see that all is dissohed
before the mi.xture
is

run
If

into
iee

the

freezer.

cream powders
be

are used, they should
first

uniformly

mi.xed with the sugar,
h'or sherbets

and
is

iees,

howe\-er,

it

best to

boil the sugar in a part

of the water to form a

simple s\rup.

The

flavoring mate-

rial, if it

be an extract, can be added at any

time
fruits
i'lfc;-

if

the mixture

is
if

not to be cooked, but or
fruit
3'J-

juices

I

l.ily

Sll.n.lL-

are

to

be

used

for
])re-

Mixer.
lla\nring,

special

cautions must

l>e

observed

in

adding

Iheni.

Fruits and fruit juices which are \cry sour must not

be .added to the ice cream or to the milk sherl)et mixture until This iirecaulion is necessary to i)revent it is partly frozen.
the acid in the fruit

from curdling the milk or cream and

PREPARING THE ICE CREAM MIXTURE
also to prevent the

89

of the freezer.

heavy fruit from settling to the bottom Ice cream containing fruit is usually colored with some appropriate color, care being taken not to add
too

much of the coloring matter. The stabilizers must be weighed

out carefully.

It

must

not be supposed that the more used the better the results.

Too much

body which is very objectionable. It must also be remembered that when such substances as condensed milk, milk powder, or homogenized cream are used in the ice cream mixture, these substances
stabilizer gives a heavy, pasty

themselves serve as stabilizers to a certain extent.

Under
need be

such circumstances
added.
starch,

little

or no other stabiHzer

In ice cream containing eggs such substances as gums, gelatins or powders are rarely used, because When properly the eggs in the mixture act as a stabilizer. cooked, these mixtures are usually sufficiently heavy so that they do not require any other substance to give body to the
product.

The cooked mixtures

differ

from the ordinary or plain

mixture, chiefly in that they contain eggs and therefore have a distinct custard flavor and a heavier body than ordinary ice cream. These mixtures require more sugar

than do the plain mixtures, because of the eggs they contain, the amount of sugar varying from 15 to 22 per cent.

In preparing the eggs and sugar for these mixtures, beat
the whites to a froth and the yolks to a cream. Add the sugar to the yolks and mix thoroughly. This mixture and the whites are then added to the cream and cooked. The cooking should be done very carefully, and must be
carried to a point

apparent.

where the raw egg flavor is no longer This will require a temperature of 175° F. to
Onei

180° F. for 10 or 15 minutes.

way

to

tell

when

the

90

ICE
is

CREAMS AND ICES
thick

mixture

by dipping a knife into it. enough to coat the knife blade, it has been cooked sufficiently. The mixture must not be cooked too long nor at too high temperature. If the cooking is not properly done the mixture will curdle, owing to the action of heat upon the egg albumen. The cooking process is not difficult and if the necessary utensils are availsufficiently is

cooked

When

the mixture

is

able

is

easily accomplished.

The flavoring, however, sometimes causes difficulty because many flavoring substances are very volatile. If such
flavoring material
is

added

to the

flavor will be driven off or very

mix while it is hot, the much modified by the heat.

Some flavors, on the other hand, should be added to the mixture while it is quite hot. Vanilla sugar may be taken as an example of this class of flavoring substance.

From

the foregoing discussion

it

will

be noticed that the

cream which have and the other does not. The same holds true of ices and sherbets; consequently, these products are also separated into two classes on account of this difference in composition. Ices and sherbets differ from ice creams in that they do not, as a rule, contain milk or cream. They differ from each other in that the ices do not contain egg albumen or any other form of stabilizer, while the sherbets contain the beaten whites of eggs and sometimes some other substances
difference between the
is

two

classes of ice

been considered

that one contains eggs

such as gelatin.
less

As

a result of this difference in composi-

tion, sherbets usually

have a better body and a somewhat
is

granular texture.
of sugar required for ices and sherbets
for ice cream, because these products

The amount

somewhat greater than

always contain fruit juices and therefore require mor^

PREPARING THE ICE CREAM MIXTURE
sweetening-.
cent.

91

The amount needed

varies

from 25

to

30 per

The

flavoring used in ices and sherbets consists of fruit
In fact, these are the only sat-

or fruit juices.

isfactory flavors that
tures.

may

r\

be used in such mix-

Where

the

mixture does not contain

may be mixed at once and placed in the freezer together, but better results will be obtained by cooking the mixture before freezing.
milk, all of the ingredients

The

objects in cooking a mixture for sherbets

or ices are to get a better blended flavor, better

body and texture, and a more complete solution
of the sugar.

Where

it is

desirable to

make

a

sherbet with a granular body, such as the granites,

the cooking should either be omitted en-

tirely or limited to

part of the water to form a simple syrup.
all

cooking the sugar in a small In

sherbets and ices, whether cooked or not, the mixture should be standardized by means of a syrup gauge. The syrup gauge is an instrument for testMore uniform and ing the density of syrups.
satisfactory results are obtained by standardiz-

Fig.

31.

A

Syrup
Gauge.
is

ing
this

all

ice

and sherbet mixtures by means of

gauge.

On

the average, the proper concentration

about 22 degrees on the syrup gauge with the temperature at 60° P., but. in some cases a lower degree of concentration
jnay be found more satisfactory.

CHAPTER IX
CLASSIFICATION OF ICE CREAM

There
ice

is

as yet no universally accepted classification of
ices,

cream,

and sherbets, although several have been

suggested and will be given here for comparison.
ice

States pure food law defines and classifies cream as follows 1. Ice cream is a frozen product made from cream and sugar, with or without a natural flavoring, and contains
:

The United

not less than 14 per cent, of milk fat. 2. Fruit ice cream is a frozen product made- from cream,
sugar, and sound, clean, mature fruits, and contains not
less
3.

than 12 per cent, of milk

fat.

Nut

ice

cream

is

a frozen product

made from

cream,

sugar and sound, nori-rancid nuts, and contains not
12 per cent, of milk fat.

less

than

This system of classification has been enlarged upon by
Professor Mortensen and a classification has been worked
out to cover
all kinds of ice creams and ices. Mortensen's classification as given in Bulletin 123 of the Iowa station, published May, 191 1, divides ice creams and

ices into ten classes as

follows:

is a frozen product made from cream and sugar, with or without a natural flavoring. " II. Nut ice cream is a frozen product made from cream and sugar and sound, non-rancid nuts.

from cream, sugar and bread products, marshmallows or other confections, with or without other natural flavoring.

" V. Parfait is a frozen product made from cream, sugar and egg yolks, with or without nuts, fruits and other flavoring.

" VI. Mousse is a frozen whipped cream to which sugar and natural flavoring have been added. " VII. Pudding is a product made from cream or milk, with sugar, eggs, nuts and fruits, highly flavored. " VIII. Aufait is a brick cream consisting of layers of one or more kinds of cream, with solid layers of frozen
fruits.

"

IX.

Lacto

is

a product manufactured from skimmed

or whole sour milk, eggs and sugar, with or without natural flavoring. " X. Ices are frozen products

made from water

or sweet

skimmed or whole milk and

sugar, with or without eggs,

fruit juices or other natural flavoring. " Ices may for convenience be divided into sherbets, milk

sherbets, frappes, punches

and

souffles.

"

I.

A

sherbet

is

an

ice

made from

water, sugar, egg

albumen and natural
of ice cream. " 2. Milk sherbert

flavoring,

and frozen to the consistency

is an ice made from sweet skimmed or whole milk, with egg albumen, sugar and natural flavoring,

frozen to the consistency of ice cream. " 3. Frappe is an ice consisting of water, sugar and
natural flavoring and frozen to a soft, semi-frozen consist-

:

94

ICE

CREAMS AND ICES
will

ency. The same formulas as are given for sherbets answer for frappe by omitting the egg albumen.

"

4.

Punch

is

a sherbet flavored with liquors or highly

flavored with fruit juices and spice. " 5. Souffle is an ice made from water, eggs, sugar and
flavoring material.
it

It differs

from sherbets mainly

in that

contains the whole egg."

It will be noticed that Mortensen's classification is on the same plan as the pure food classification of ice cream but is more complete. Since the pure food law recognizes the first three classes of ice cream, there may be some advantages in this system of classification. But in classifying according to flavors the whole system tends to become very

complicated.

of classification.

The present need is for a simpler system The system may be simplified by classify-

ing according to certain fundamental differences in composition

and method of manufacture rather than the kind
is

of flavoring material used.

This difference in composition
in Bulletin

recognized by

Washburn

155 of the Vermont station. Although a full classification is not attempted, his comment on the different

kinds of ice cream

is

quoted _here because he views the
is

subject from a different angle.

Washburn's
"
I.

classification

as follows

Plain ice cream, frequently known as Philadelphia

and, occasionally, as the

New York

ice

cream

;

a plain and

raw

article,

rarely or never containing eggs, being

com-

posed simply of cream of variable butter fat content, sugar in uniform quantities, and almost always containing gelatin
or some other gelatinoid binder (stabilizer).
"
2.

The French

or Neapolitan ice cream, which con-

tains eggs in addition to the

cream and sugar,

is

virtually

:

CLASSIFICATION OF ICE CREAM
Washburn's
logical because
classification is obviously simpler
it

95

a frozen custard and as such admitting of great variation."

and more
diiifer-

recognizes a real and fundamental

ence in the composition and method of manufacture.
classification

A

worked out by Larsen and White,^ following this same idea, is given below with some modification in wording, but essentially the same as given by them. Larsen and White's classification of ice cream and ices " I. Philadelphia ice cream is an ice cream made from cream, sugar and flavoring, and usually contains a binder (stabilizer). This class includes not only plain ice cream and chocolate, coffee and macaroon flavors, but nut and fruit ice cream as well. " II. Neapolitan ice cream is an ice cream made from This kind of ice cream sugar, flavoring, and eggs. cream, may resemble a frozen pudding in composition and consistency.

" III.
ice

Fancy

ice

cream

chiefly in the

cream differs from the Philadelphia manner of molding, printing and

coloring.

" I. Brick ice cream is usually made up in pint, quart and two quart sizes, and in two oi' more layers. Any of the ice creams may be used for this purpose. " 2. Individual molds are shaped to imitate some object (fruit or animal) and may be colored in imitation of the

object it represents. " IV. Ices are made from fruit juices diluted, sweetened

and frozen.
"
I.

Water

ices are

made from

fruit juices diluted to the
ice

proper degree, sweetened and frozen the same as but are more or less grainy in texture.
1 "

cream,

Milk Technology."

96
"
2.

ICE

CREAMS AND

ICES
juices, water, sugar,

Sherbets are composed of fruit

white of eggs and sometimes a binder (stabilizer). They sometimes resemble ice cream in appearance, body and texture.

"

fine,

"

Sorbet is a name sometimes applied to sherbets of smooth texture. 4. Granites are water ices only half frozen without much
3. 5.

stirring.

"

liquors or cordials like

Frozen punches are made by adding one or more champagne, maraschino or Jamaica
is

rum

to a water ice or sherbet, usually after the freezing

nearly or entirely completed."

Aside from
fication

its
it

other advantages such a system of classieasier for the beginner to

makes

form a general

idea of the nature and composition of the different kinds of
ice

creams and

ices,

groups.

The

ice

because they are confined to a few creams and ices of any one group being
it

similar in

composition,

is

easier to

remember

certain

formulas or to look up any formula wanted by referring to
a certain class.

Since the classification just given very nearly meets our
present needs,
it

will

be followed in this work with only be necessary to make
it

such modification as
throughout.
of one

may

uniform

This modification will consist of the addition
class

more
is

and the rearrangement of the
of the class to be added.
is

classification

of ices and sherbets.

Mousse
for

the
this

name

The

reason
in

adding

product

because of
ices

its

difference

composition and method of manufacture.

The

difference

between

and sherbets

is

that the

former do not contain egg albumen or a
latter do.

stabilizer but the

In addition to this the sherbets are sometimes

:

CLASSIFICATION OF ICE CREAM
made with sweet
or sour milk instead of water.
that the system of classification

97
In order

may

be uniform through-

out, a slight alteration is suggested for the classification of

and sherbets. With these alterations included the system of classification adopted by the dairy department of the University of Nebraska is as follows Suggested classification of ice creams and ices. " I. Philadelphia ice cream is ice cream made from cream, sugar and flavoring, with or without a stabilizer. " II. Neapolitan ice cream is ice cream made from cream, sugar, flavoring and eggs. These may resemble frozen custards or pudding in flavor, composition and conices

sistency.

" III.

Fancy molded

classes chiefly in the
ing.

ice cream differs from the above method of molding, printing and colorclass

For convenience the
I.

may be

subdivided as

fol-

lows:
"

Brick ice cream

is

molded

in brick

molds of

pint,

quart or two quart sizes and usually consists of two or more
layers of different flavors and colors. " 2. Individual pieces are molded in the
object, such as fruits or animals,

form of some and are usually colored to
flavored,

imitate the objects which they represent. " IV. Mousse is a rich cream, sweetened,

whipped to a stiff froth and frozen, usually in a mold but sometimes in an ordinary ice cream can. " V. Water ices are fruit juices diluted with water, sweetened and frozen without a stabilizer of any sort. In this class may be included granites, which are water ices
frozen with but
little

agitation

;

frappe, a partly frozen ice

having a slushy consistency. " VI. Sherbet is a frozen product made of

fruit juices,

98

ICE

CREAMS AND
It

ICES
gela.-

water or milk, sugar and eggs.
tin or

sometimes contains

some other

stabilizer.

Sherbets

may

be subdivided

as follows: " I. Plain sherbets

made from

fruit juices, water, sugar

and
egg

eggs, with or without a stabilizer.
is

When
it is

the whole

used, these sherbets are sometimes called souffles.
liquor or spice
is

When
punch.

added

to a sherbet

known

as

" 2. Milk sherbets made from fruit juices, milk, sugar and eggs, with or without a stabilizer. The milk used may be either whole or skimmed. " 3. Lactos are milk sherbets made from sour milk or

may be taken as representative of these different classes. By keeping the above system of nomenclature in mind it
will

be easier by association to remember the more important formulas or to find the others by referring to the proper
in the book.

group

:

CHAPTER X
ICE

CREAM FORMULAS

Philadelphia Ice

Cream
all ice

The
las

following formula
this class.

may

be taken as a basis for

creams of

In

this, as in

most of the other formuproperly frozen.

given here, the quantities specified will make approxiice

mately ten gallons of

cream,

if

Vanilla Ice

Cream

40
8

lbs.
lbs.

17% cream
sugar
(if
if

4

oz. vanilla extract oz. gelatin

4
This mixture
tests

desired)

14% and

properly frozen will give

an ice cream of good body and texture.

The above formula

may

be used with such flavors as chocolate, caramel, nuts

and fruits or fruit juices. Bisque ice cream. This is a Philadelphia ice cream to which finely chopped bread products, marshmallows or some It will be necessary to similar substance has been added. use a richer cream if the mixture is to test 14 per cent. The formula would then be as follows

40
8

lbs.

19% cream
sugar

lbs.

4
4
5

oz. vanilla extract oz. gelatin (if desired)
lbs.

of some bread product or confection
99

100

ICE

CREAM AND

ICES

This formula admits of quite a wide variety of flavors. may be macaroons, crumbs of lady finger cake, sponge cake, Nabisco wafers or similar cakes.
Tlie bread products used

By adding about
extract,

four ounces of vanilla sugar instead of the

and scalding the cream, a very mild but rich and pleasing flavor will be obtained. Blended flavors. It is sometimes desirable to add one or more secondary flavors to modify the principal flavoring
agent in order to obtain the best results.

Chocolate ice cream.

The

process of blending flavors

is

well illustrated in the following formula for chocolate ice

cream, in which vanilla or cinnamon out a more pleasing chocolate flavor.

may be used

to bring

40 8

lbs. lbs.

iS^o

cream

sugar

1^2 lbs. bitter chocolate^ 2 oz. vanilla extract or i}4 oz. cinnamon

4

oz. gelatin

(if desired)

with favor wherever quality
is

This gives an excellent chocolate flavor and should meet is appreciated. If the cinnamon
used instead of the vanilla,
:

it

should be prepared as

fol-

lows

cover,

Pour a and let

half pint of boiling water over the cinnamon,
it

stand for half an hour in a

warm

place.

Strain off the clear, hot liquid and
to

work

it

into the chocolate

form a smooth

paste.

Scald the cream and work the
Strain and cool to a very low

chocolate paste in while hot.

temperature and
ing.

let it

stand for several hours before freez-

1 quart of chocolate syrup or a mixture of equal parts of bitter chocolate and cocoa may be used instead of the bitter chocolate. See

A

page

66.

ICE

CREAM FORMULAS

loi

Prepared chocolate flavor may be obtained from manuform of a paste or as a syrup which can be worked into the cream while cold, thus avoiding the necessity of scalding the cream in order
facturers of ice cream flavors, in the
to incorporate the flavor.

may

Cocoa. A cheaper and fairly satisfactory chocolate flavor be produced by using cocoa and caramel syrup. For

ten gallons of ice cream take a half pound of good cocoa and four ounces of caramel syrup. Mix the cocoa with the sugar and a4d the caramel syrup and about a quart of simple syrup. Mix all together and bring to a boil. Strain and cool the mixture before adding it to the cream. Caramel ice cream is flavored with caramel syrup blended with vanilla. The color of this ice cream should be a very light brown and sufficient caramel syrup should be added For ten gallons of ice cream to give the desired result. it will require approximately 12 ounces of syrup and three

ounces of vanilla extract.

The caramel
is

flavor blends nicely

with various other flavors and

also used for coloring ice
color,

creams which require a
cream.

light

brown

such as maple

ice

Maple ice cream may be made by using maple extract and enough caramel syrup to give the desired color, but this ice cream lacks the fine quality of the ice cream flavored with maple sugar or maple syrup. The best quality of maple is made by substituting two pounds of maple sugar or a quart of maple syrup for two pounds of the granulated sugar. Two ounces of vanilla and two or three ounces of caramel should also be used to bring out the flavor and a light brown
color.

All of the fomiulas given above are calculated on the
basis of

14 per cent,

fat,

because the pure food law in

:

102

ICE

CREAMS AND
amount of
is it

ICES
fat.

many
ice
is

places calls for that

There are some

places,

however, where
less

permissible to manufacture

cream containing
desired to

make such

ice

than 14 per cent. fat. Where it cream, the following formula

may
class.

be used as a basis for ice creams of the Philadelphia

A

mix containing condensed

milk.

An

ice

cream of ex-

having a good body and a very smooth texture, may be made by using condensed milk and some whole milk in the mixture. The cream, condensed milk, and whole milk are mixed in the proportion of six parts cream,
cellent flavor,
five parts

bulk condensed milk and four parts whole milk.

On

this basis a

mixture for ten gallons

may

be prepared

as follows

16

lbs. lbs.

20% cream
condensed milk (8 to 4% milk sugar

14 8

10%

fat)

II lbs.
lbs.

4 4

oz. vanilla extract

oz. gelatin

This mixture will
fat.

test 9.5

per cent, to 10 per cent, butter

Owing

to the presence of the

rich in solids not fat, this ice

value,

and theoretically
ice

at

condensed milk, which is cream has considerable food least, would have a more cooling

effect because of the

lower fat content.

Nut

given above with very

cream may be made from any of the formulas little alteration. The nuts must be

prepared carefully to obtain the best results. Nuts, such as Brazils, which are very oily, should not be used. In all
cases
it is

well to add a

little salt

to the nut ice creams.

A

half teaspoonful of salt to a gallon of

mix

is

sufficient.

ICE

CREAM FORMULAS
and then
is

103

Certain kinds of nuts must be blanched by dropping them
first into

boiling water

into cold water, after

which

the dark outer skin of the nut

easily

removed.

Walnut
40
8
lbs.
lbs.

Ice

Cream

18% cream
sugar

2 oz. vanilla extract

4 4

lbs.

walnut meats

oz. gelatin (if desired)

Preparing the nuts. Use only sound, non-rancid nuts. They should be run through a meat mincing machine and added to the ice cream when it is partly frozen. If the

cream is not partly frozen the nuts will settle to the bottom of the freezer and will not be evenly distributed through
ice

the mixture.

An

equal amount of any other nuts
if filberts,

may

be substituted for

the walnut meats, but

hazelnuts, almonds or pis-

tachio nuts are used they should
74-)

first

be blanched.

(See page

Pistachio Ice

Cream

40
8

lbs. lbs.

18% cream
sugar

3 lbs. pistachio nuts

4
I

oz. gelatin oz.

almond extract

Color the mixture a pale green.

Almond and

pistachio flavored ice creams

may

be

made

without the use of nuts by adding the required amount of

104

ICE

CREAMS AND
extract, but to

ICES
make
the best quahty

almond or pistachio
extract

of ice cream, nuts should be added.

A

small

amount of the
howeve;r,
is

may

be

added
is

to

the

ice

cream,
ice

to

strengthen the flavor.

The almond

cream

white.

The

color of pistachio

a very light green.

Fruit ice cream.

The
all

following formula, which

is

a

good example
fruit.

of fruit ice

cream, will serve as a guide to

the preparation of

Philadelphia ice creams containing

Strawberry Ice Cream
40 8
4
lbs.

18% cream
sugar

lbs.

qts.

crushed berries
(if desired)

4 4
Select sound,

oz. true "Itrawberry extract oz. gelatin

mature

fruit of a

deep red color.

Clean,

add part of the sugar

and mash thoroughly. Mix the other ingredients, and when partly frozen add the crushed fruit and complete the freezing.
to the berries

Pineapple, peach, apricot, cranberry,

etc.,

may

be used

instead of strawberry, adding sugar as needed.

Use of preserved fruit. During that season of the year when fresh fruit cannot be obtained, preserved fruit may
be used, but the flavor should be strengthened by the addition of flavoring extracts,

and the acidity increased

by,

adding the juice of two lemons to each gallon of fruit used. Care must be exercised in preparing the lemon juice not to
get any of the oil
this,

from the rind

into the juice.

To

avoid

peel the lemons carefully,

removing

all

of the white

inner portion of the rind before pressing out the juice.

The

reason for this precaution

is

that a very

little

of the lemon

;

ICE
oil

CREAM FORMULAS
impart a lemon flavor.
is likely is

105

in the juice will

Even a small

amount
lemon

of the white, inner rind

to give the juice

a bitter flavor.

The lemon
fruit..

juice

used, not to impart a
fruit acid in

flavor, but to increase the

amount of
in this

the preserved

Ice cream

made

way

closely

resembles that

made from
orange
ice

the fresh fruit.

with the extract only, but the

cream may be made by flavoring finest ice cream of these flavors should be made from the fruit without any extract at all. For lemon ice cream grate the rinds from a few of the lemons, add a little of the sugar, and mix together thoroughly so that the sugar will absorb the oil from the rind. Only Squeeze the very outer part of the rind should be used. enough lemons to give the desired amount of juice, dissolve Orange juice is the sugar in it, and strain before using. sweeter and milder in flavor and blends nicely with the lemon
so that a

Lemon and

more pleasing
is

flavor

is

obtained

if

a small quantity
flavor.

of orange juice

used to modify the sharp lemon
peeled before being pressed.

The oranges should be

The

other ingredients are mixed in the proportions given in the

following formula for five gallons of ice cream.

20
1

lbs.

18^0 cream

5 lbs. sugar
pt.
pt.

lemon juice
orange juice
(if desired)

y2

2

oz. gelatin

Orange

ice

cream may be made by

following the same

formula, but the sugar should be reduced to four pounds. Use one quart of orange juice and about four ounces of
Peel the lemons carefully before squeezing, but grate the orange peel and mix it with a part of the sugar

lemon

juice.

io6

ICE
juice,

CREAMS AND

ICES

add the add the

of the sugar with the cream and
fruit juices

mix thoroughly, and strain. Mix the rest when it is partly frozen
and complete the freezing as for any
of fruit juices

other ice cream.

The amount

may be

reduced
If

somewhat by strengthening the

flavor with an extract.

made with

fruit juices only, this ice fruit
if

under the head of
contain 14 per cent,

12 per cent, fat, but

cream should come ice cream and need contain only flavored with an extract it must creams (for
five gallons

fat.^

Other Philadelphia
cream).

ice

of ice

Banana
20
lbs.

18% cream
sugar

4^

lbs.

banana pulp Juice of 5 lemons
5 lbs.

2 oz. gelatin (if desired)

Cook the cream and
before freezing.

half of the sugar and cool thoroughly

Mix

the rest of the sugar with the banana
it

pulp and lemon juice and add

to the cream

when

the

mixture

is

partly frozen.

Raspberry
20
5
lbs. lbs.

18% cream
sugar
raspberry juice

5

qts.

2 oz. gelatin (if desired)
First method.

Dissolve the gelatin in a
;

little

warm

milk

and
this
2

stir it into

the cream

mixture

is

add the sugar and freeze. When partly frozen add the fruit juice. A better
effect.

In States where fat standards are in

See Appendix.

ICE
texture

CREAM FORMULAS

107

may

be obtained, however, by the method given

below.

Second method.
the gelatin.

Cook

half the sugar, the

cream and

Cool thoroughly and freeze this mixture. Press the juice out of the fruit, add the rest of the sugar, and cook to a clear syrup strain, and when cooled beat it into
;

with the extract of peppermint or wintergreen. The peppermint ice cream is usually colored a very light green and
wintergreen a very light pink.
Coffee ice cream

may be made by adding
for

three pints of

and enough caramel syrup to give it a light brown color. Another method which gives better results when properly carried out is as follows For 5 gallons
very strong coffee to the mixture
ten gallons,
.

20, lbs.

18% cream
sugar

4
Yi

lbs.
lb.

Mocha

coffee

2 oz. gelatin

Heat about

half the

the coarsely ground coffee.

stand for 15 minutes.

cream and when it is very hot add Cover the mixture and let it Then strain it add the flavored cream
;

ICE

CREAM FORMULAS

109

to the rest of the cream.

Cool the mixture thoroughly be-

fore freezing

it.

Neapolitan Ice Cream

The following formula may be taken
Neapolitan
ice

as a basis for

all

creams.

For 10 gallons:

40
8

lbs.
lbs.

20% cream
sugar

7 doz. eggs
5 oz. vanilla

Preparing and cooking the mix.
Beat the whites to a
stiff

Beat the yolks of the
stir

eggs to a smooth cream, add the sugar and beat again.
froth

and

them

into the yolks
stir

and sugar.

IVIix this

with the cream and

constantly

while cooking.

Cook

for 15 to 20 minutes or until the mix-

and does not run.

ture will just slightly coat a knife blade dipped into it, It will require a temperature of 180° F.
for about 15 to 20 minutes to accomplish this.
If

cooked
likely
it

too long, or at too high temperature, the mixture
to curdle.

is

When

the mixture

is

cooked, strain and cool

thoroughly before freezing.

Kinds

of flavors to use.

Such

flavors as vanilla, coffee,

caramel and the various nut flavors are best adapted to the Neapolitan ice creams, as the fruit flavors do not harmonize so well with the eggs. If so desired, however, the fruit flavors may be used in Neapolitan ice creams.
chocolate,
It will

fruit juice

only be necessary to slightly increase the amount of used in Philadelphia ice cream and then follow

the instructions given above for Neapolitan ice cream. French cooked cream. The following formula for French

cooked cream

is

ysed in some factpries as a basis for various

no

ICE CREAjMS
all

and

ICES
would be
classified

kinds of special ice creams,
as Neapolitan ice cream.

of which

40
12

lbs.

20%
sugar

cream

7 doz. eggs
lbs.

(This mixture will test about isVzfo to 16% fat.) Beat the yolks to a cream, add the sugar, and beat a little

smooth texture. Whip the whites to a froth and Heat the cream, stir in the eggs and the yolks. sugar, and cook as for Neapolitan cream strain the mixture and cool it at once.
to get a

mix with

;

Tutti Frutti Ice
5 gal.

Cream

French cooked cream

8 2 2 2

oz. vanilla extract
lbs. lbs.
lbs.

ground nuts
cherries

assorted candied fruit

Colored pineapple cubes are

now used

to a considerable

extent commercially as a substitute for cherries.

Nesselrode Pudding

4 6
2 2 J4

gal.

French cooked cream
candied cherries
raisins

oz. vanilla
lbs. lbs.
lb.

citron

2 2 2

lbs.
lbs.

walnut meats
blanched almonds
filberts

lbs.

ICE
Chop the

CREAM FORMULAS

in

fruit fine
in

Grind the nuts

and boil in simple syrup until tender. a meat mincing machine and add all to

the partly frozen cream.

Manhattan Pudding
3 gals. 30% cream 7 doz. eggs 12
lbs.

^

sugar

2
1

qts.
pt.
lbs. lbs.
lbs.

orange juice

lemon

juice

2 2 2

walnut meats pecan meats
assorted fruits

3

Plum Pudding ^ gals. 30% cream

10 2
I

7 doz. eggs lbs. sugar
ij4
lbs.

chocolate

lbs.
lb. lb. lb.

assorted fruits
raisins
figs

I
1

walnut meats

2 tablespoonfuls of ground cinnamon
y-2.

teaspoonful ground cloves

Frozen Custard
(For
five gallons)

20
7!/^

lbs.

20% cream
sugar
vanilla sugar

5 doz. eggs
lbs.
lb.

J^
3

Bui.

123

Iowa

station.

112

ICE CREAiMS

AND

ICES

Put two-thirds of the cream into a double boiler over a fire. Beat the eggs and sugar to a smooth cream and add them to the hot cream; cook the mixture until it Take it from the fire, add the rest of will coat a spoon. Strain and chill the mixture the cream, and stir until cold.
quick

thoroughly before freezing

it.

Almond
20

Pistachio Ice

Cream

(For
lbs.

five gallons)

18% cream

2.Y2

doz. eggs

5 lbs. sugar

2
I

lbs.

blanched almonds
extract

oz. pistachio

3 oz. vanilla sugar

Prepare the eggs, sugar, vanilla sugar, and cream, and cook as for Neapolitan. (See page 109.)

Burnt Almond Ice Cream
(For 20
2,y-2

five gallons)

lbs.

18% cream

doz. eggs

5 lbs. sugar
I

lb.

almonds

Prepare the almonds according to either of the two folBlanch the almonds. Place them on a lowing methods baking tin and set into a quick oven to roast until they are
:

a golden brown.

Pound the roasted nuts in a mortar with an equal weight of sugar and enough cream to form a smooth paste. The other method is to put the blanched
almonds with an equal weight of sugar into a porcelain

ICE

CREAM FORMULAS
is

113

lined kettle or earthenware bowl,
stirring until the sugar

and set over a hot fire, melted and coats the nuts all over.

Pour them on a buttered dish to cool. When the nuts and sugar are cold and hard, grind in a mortar and sift through a wire sieve. Repeat the operation till the nuts are all finely
powdered. Mix the paste or the powder with the cream before cooking the mixture.
Butter Ice Cream

equal amount of cream and sugar to a smooth paste, and mix with the butter. Grate the rind of the lemon and mix

with a
strain

little
it

sugar; dissolve this in a part of the cream and
;

cream add the sugar and eggs, cook and cool the mixture as directed. When the mixture is nearly cold pour it in a fine stream into the butter and stir If well until a smooth, well-blended mixture is obtained.
into the rest of the

the cream

is

more than luke warm

it

will

melt the butter, Color
it

making
yellow.

it

impossible to get a good mixture.

pale

114

ICE

CREAMS AND

ICES

Chestnut Ice Cream
(For
five gallons)

20

lbs.

i8% cream

2J/2 doz. eggs

5 lbs. sugar
I lb.

chestnut pulp

3 oz. vanilla

sugar
(If

2 oz. gelatin

desired)

Peel and boil enough chestnuts to yield one pound of
pulp.
to

Grind them

in a

make a smooth

paste.

mortar with enough sugar and cream Cook the mixture as directed.

CofTee Ice

Cream

(For 20
lbs.

five gallons)

18% cream

2)^ doz. eggs 5 lbs. sugar
1
lb.

Mocha

coffee
(if

2 oz. gelatin

desired)

half the

Grind the coffee very fine and cook for ten minutes with cream strain and add to the other half of the cream. Prepare the eggs and sugar, add to the cream, and cook as
;

directed.

Filbert Ice

Cream

(For 20
lbs.

five gallons)

20%

cream

2j^ doz. eggs 5 lbs. sugar
2
lbs.

shelled filberts

ICE

CREAM FORMULAS
oz. gelatin
(if

115

3 oz. vanilla sugar

2

desired)

Blanch the nuts and roast to a rich brown color. Grind little sugar and cream to form a smooth paste. Color it a light buff.
the nuts in a mortar with a

Beat the whites to a froth, add the powdered sugar and whip until stiff and smooth. Pound the cake very fine, and sift. Cook the cream, sugar, yolks and vanilla
sugar, and strain into the freezing can.
chilled,

When

thoroughly

beat in

add the sifted cake, and freeze. Open the can and the egg whites, working the batch until smooth.

Hokey Pokey is a frozen product made from milk, cream, condensed milk, gelatin, sugar and flavoring. Two formulas are given here to show the general characteristics of " hokey pokey," " frozen dainties " and allied products.

ii6

ICE

CREAMS AND
Hokey Pokey
I

ICES

(For about eight gallons)

40
}4
I

lbs.

4%

milk

2 doz. eggs
lb.

corn starch

gal.

condensed milk
sugar

6 oz. gelatin

9

lbs.

6 oz. vanilla extract
Boil the corn starch and add
it to the mixture of milk Beat the eggs to a cream and add them

and condensed milk.
to

the milk.

Cook the mix

until

it

will
it

coat

a

spoon.

Strain and cool the mixture and freeze

at once.

Hokey Pokey
3J^
gal.

II

(For about eight gallons)

4%

milk

1/4 gal. 20% cream 2 lbs. milk powder

8

lbs.

sugar

6 6

oz. gelatin oz. vanilla extract

Mix
milk.

the milk

Add

the melted gelatin, strain,

powder with the sugar and dissolve it in the and freeze the mixture

at once.

and similar occasions, hokey pokey is put up in These quart bricks are then cut in six or Each eight slices. slice is wrapped in waxed paper or parchment and packed in a brick tank. Goods of this sort should be sold for just what they are a less expensive grade of ice cream. The poor materials used in "the hokey pokey sold by many street vendpicnics

For

quart molds.

—

ICE

CREAM FORMULAS

117

ers has given rise to considerable prejudice against frozen

products of this kind.

Fancy
in

Ice

Creams

Fancy ice creams differ from those already mentioned, the method of manufacture rather than in composition.
is

If there in the

any difference

at all in composition,

it

is

usually

amount of
It is

stabilizer or the richness of the
ice

used.
it

very important in making fancy

cream cream that

be so

made and
it

frozen that the molded cream will retain

removed from the mold. For this reason more stabilizer or a richer cream is sometimes used.
its
is

shape after

The

principal difference between fancy ice cream and ordinary bulk ice cream, however, is in the manner of packing. Brick molds of various capacity, large fancy molds for

molding ice cream in the form of a statue or some other and small incUvidual molds holding enough ice cream for one service are the usual forms in which the fancy ice cream is put up. Special formulas are sometimes used for fancy ice creams and ices, largely because this kind of ice cream is often made to order. The ice cream maker who has some originality and a little artistic talent can easily work up a large and very profitable trade by preparing a specially molded, flavored, and colored ice cream or ice for special This, however, is a subject of sufficient imoccasions. portance to warrant its treatment in a separate chapter. (See Chapter XII.)
object,

Mousse
This
is

a frozen whipped cream.
its

It

is

given here as

a special class because of

difference in composition

and

method of manufacture.

ii8

ICE CREAAIS
to be used in
will

AND

ICES

making mousse must be of such whip to a stiff froth. The richness of the cream as well as the method of making may have to be varied somewhat with different flavors. The flavors which may be used are vanilla, coffee, caramel, almond, pistachio, maple and various fruit flavors. When the extract flavors are used, the directions for whipped cream may be followed until the mousse is ready to pack. The freezing is accomplished without agitation by packing the whipped cream in a mold or a can surrounded by equal parts of ice and salt. To obtain good results it will be necessary in many cases to use gelatin, particularly where fruit
richness that
it
.

The cream

is

used quite

liberally.

The

following formulas

may

be

taken as representative of this class of frozen products.

Peach Mousse
(For about
2
I

five gallons)

gals.

35%

cream

gal. sifted oz.

4 4 4

peach pulp lemon juice

to 5 lbs. sugar
oz. gelatin

ing water and add
thicken.

Soften and then dissolve the gelatin by heating over boilit to the fruit juice. Dissolve the sugar

in the fruit juice; chill

and

stir

the mixture as

it

begins to

Whip

the cream until

stiff

and

fold

it

into the fruit

mixture very carefully. Pack it in ordinary ice cream cans or molds to harden. By following these same directions

any other

fruit flavor

may be

used.

Where

fruit juice of slight acidity is

used instead of the

pulp, the following

method may be

substituted.

ICE

CREAM FORMULAS
Strawberry Mousse
five gallons)

119

(For about
2 gals.
J4
gal.
lbs.

40%
sugar

cream

strawberry juice.

4
2
Press the
strain,
fruit,

oz. gelatin

heating

if

necessary to start the juice,

and add the sugar and the melted gelatin. Chill both the fruit and cream before mixing and whip until stiff. Pack in molds or freezing cans surrounded with equal parts of ice and salt.
Pineapple Cream Souffle

(For about
2 gals.

five gallons)
*

40% cream

6 qts. pineapple juice 8 lbs. sugar Yolks of 5 doz. eggs

4

oz. gelatin

Beat the yolks and part of the sugar to a cream. Add the and cook to a clear syrup. Add the hot syrup to the beaten egg yolks. Strain the melted gelatin and add it to the mixture. Whip the mixrest of the sugar to the fruit juice

ture until

it is

stiff

and well swollen.

Set

it

in

a refriger-

ator or ice cave until well chilled.

Then add

the whipped

cream, which should be lightly stirred in but not beaten.

The mixture
mousse.
It

is

packed and frozen the same as ordinary
to serve

sometimes happens that a customer desires

these desserts, with a sauce.

In that case the sauce should

correspond in flavor with the frozen dessert.

The

follow-

120
ing sauce

ICE

CREAMS AND ICES
served with the pineapple cream souffle

may be

described above.

Sauce for Souffles
Yi gal.

20%

cream
doz. eggs

10 oz. sugar

Yolks of
I

i^

pt.

pineapple juice

Juice of one lemon

Color yellow,

if

desired

the cream to form a soft custard.

Beat the egg yolks and sugar until smooth and cook with Chill the mixture and stir in the fruit juices; then pack in ice without salt until

needed.

Vanilla Biscuits
10 qts. whipping cream 60 &gg yolks
"jYs.

lbs.

sugar

2

pts.

water

3 oz. vanilla sugar

Cook the sugar and water to a clear syrup add the beaten egg yolks- and the vanilla sugar. Strain the mixture and beat it until it is cold and quite stiff. Whip the cream to a
;

stiff

froth and stir

it

into

the cold mixture.
set

Place the

mixture in molds or paper cases and
to harden.

them

in

an

ice cave

Almond

Biscuits

10 qts. whipping cream 60 &gg yolks

ICE
6
2
1

CREAM FORMULAS
lbs.

121

sugar

pts.

water

oz.
lbs.

2

almond extract blanched almonds

Cook the sugar and water to a clear syrup. Pound the almonds and almond extract to a smooth paste. Beat the egg yolks to a smooth cream. Add the nut paste and the eggs to the hot syrup and stir it until the mixture begins to thicken. From this point on the process is the same as
for vanilla biscuit.

Cherry Biscuits
10
qts.

whipping cream

60 egg yolks
5 qts. cherry juice

10

lbs.

sugar

3 oz. gelatin

Beat the egg yolks and the sugar to a smooth cream
the cherry juice and cook the mixture until
it

;

add

coats a spoon.

Dissolve the gelatin in the smallest possible amount of

warm

water and add

it

to the cooked fruit juice.

Strain and
froth and

cool the mixture.
stir it lightly into

Whip

the cream to a

stiff

the fruit custard.

Any

of the above mixtures

may be

frozen up as directed

or the biscuits
that way.

may

be glazed with meringue and served in

CHAPTER
WATER
ICES

XI

AND SHERBETS
Ices
strictly dairy

Water
Water
ices

and sherbets are not

products
ices are

as they do not always contain milk.

The water

made from
frozen.

fruit juices diluted

with water, sweetened, and

Sherbets have practically the same composition but
ices are of variable

contain in addition egg albumen and sometimes gelatin.

Water
being

composition and richness, some

made almost

entirely of fruit juices highly sweetened

and frozen, while others are very much diluted and lightly flavored and sweetened. As a rule these ices have a more
or less granular texture.

The

following formulas are given

as characteristic ices of the simplest kind.

Lemon
10
lbs.

Ice

3 gals, water

sugar

3 pts. lemon juice

Mix all the
the freezer.

ingredients.

When the sugar is
this is

well dissolved,

freeze the mixture until fairly firm before removing
It will

from

be seen that

nothing but a frozen

lemonade.
ture.

A pint

of orange juice would improve the mix-

Orange ice is made by using three pints of orange juice and a half pint of lemon juice with the Other constituents as
given above.
122

WATER

ICES

AND SHERBETS

123

Pineapple Ice
3 gals, water 10-12 lbs. sugar
I
Yi.

pt.

lemon juice
grated pineapple

gal.

Preparing the fruit. In preparing the lemon juice for mixture peel the lemons carefully, cut them in halves, and remove the seeds before squeezing. The pineapples must be thoroughly ripe and juicy. Pare them and remove the cores, crush or grate them, and strain
this

the pulp.

The

juice should be used as soon after

it

has
fruit

been prepared as possible. Preserved fruits, dried
juices

fruits, jellies

and prepared

may

be used

if

fresh fruits are not available, but

the resulte as a rule are not so satisfactory.

As

ordinarily made, ices are

more or

less

granular in

by a little extra work in preparing and freezing the mixture it is possible to make an ice with a very smooth texture. To make ices of very smooth texture the sugar and water should be cooked to a clear syrup, strained, and cooled. The prepared fruit juice is then added and the mixture frozen by packing with a slow freezing mixture (i to 15) and running the freezer at high speed for 15 to 20
texture, but

minutes.

Freezing and packing. The texture a given batch of ice will have when finished will depend to a considerable extent upon the manner of freezing and packing. Rapid
freezing and
freezing with but
little

agitation,

tend to

produce

3.

coarse, granular texture.

Cooking, as described

:

124

ICE

CREAMS AND

ICES

above, with slower freezing and thorough agitation, tend to

produce a
It will

finer texture.

.

be noticed that

ices contain

no

stabilizer of
will

any
be

sort; consequently, they melt very rapidly

found much more
condition.

difficult to

and it keep them packed
salt

in

good

The

ice

used

in

packing should be finely crushed
than
is

and should contain somewhat more
ing ice cream.

used in pack-

Sherbets
Sherbets, as usually made, are very similar to the ices, both in flavor and appearance, but differ from them in
composition.

The

sherbets always contain eggs and fre-

quently a stabilizer also, but the ices do not.

By

careful freezing and proper packing sherbets
ice

may

be

made to resemble The fine texture of

cream
is

in

appearance and texture.

sherbets

due to the egg albumen and

other stabilizers used in the mix.

Lemon and orange
of one dozen eggs. follows

sherbet

may be made by

following

the formula given for ices with the addition of the whites

The formula should

therefore be as

Lemon
(For about

Sherbet
five gallons)

3 gals, water

lo

lbs.

sugar

3 pts.
1

lemon juice
orange juice

pt.

Whites of I doz. eggs 2 02. gelatin (if desired)

:

WATER
part of the sugar,

ICES

AND SHERBETS

125

Grate the rinds of about six of the lemons, add it to a mix well and add this mixture to the fruit juices. The water and the rest of the sugar should

be cooked to form a clear syrup and cooled.
juices should then be

The

fruit

added and the mixture strained and standardized to a density of 20 degrees on the syrup gauge. The tgg whites should be beaten to a stiff froth and may be added to the mixture when it is placed in the
freezer.

A
hot,

second method of making sherbets, which gives splen-

did results but requires

more

time,

is

as follows

Cook

the sugar and water to a clear syrup, strain while

and set away to cool. Add the prepared fruit juices and the other constituents, except the whites of the eggs, and
freeze for about 15 minutes.

Add

12 teaspoonfuls of finely

powdered sugar
stiff froth.

to the whites of the eggs

Open
;

the freezer, scrape

the beaten eggs

stir

pack the freezer and

them in set away

and beat to a and add thoroughly until smooth. Re-

down

the can,

to harden.

Pineapple Sherbet

(For

five gallons)

3 gals, water Whites of 12 eggs 12
1 J/2

lbs.

sugar

pt.

lemon

juice

gal.

grated pineapple
(if

2 oz. gelatin

desired)

Follow the directions given for lemon and orange sherbet, but be sure to remove the peel of the lemons before squeezing
them.

:

126

ICE

CREAMS AND

ICES

considerable
giving,
is

Thanksgiving Day special. A sherbet for which there is demand on certain occasions, such as Thanks-

made

as follows

(For about

five gallons)

3 qts. cranberries

12

lbs.

sugar

3 gals,

water Whites of 12 eggs

2 oz. gelatin
Boil the cranberries, sugar, and water.

When

the berries

add the melted gelatin, cool, adjust the density of the mix to 20 degrees on the syrup gauge, and freeze. When the mixture is partly frozen, work in the beaten whites and stir until the whole batch is smooth and uniform throughout. Other sherbets may be made according to this formula by substituting the proper fruit juice. Some of the fruits that are only mildly acid must be used in larger amounts. As a rule such fruits as strawberry, peach, cherry and any other fruits of mild acidity may be used at the rate of one
;

are cooked strain out the juice

quart of crushed fruit or fruit juice to the gallon of water.

In connection with these, lemon juice should be added at
the rate of

2^

ounces to the gallon of water, sugar at the

rate of three to four

pounds

to the gallon of water,

whites of four eggs for each gallon of water.

and the Except in

lemon sherbets and where otherwise noted, the peel of the lemon and the seeds should be removed before squeezing.
Freezing.
It requires

erly than to freeze ice cream, but

more time to freeze a sherbet propwhen properly frozen the
alike in appearance

two

will

be very

much

and texture.

WATER

ICES

AND SHERBETS

127

Sherbets will not stand up well unless packed very carefully in very finely crushed ice containing somewhat more
salt

than

A

is used for ice cream. general formula which may be used as a base for is

all

sherbets

as follows

:

(For about

five gallons)

3 gals, water or milk

10
I

lbs. pt.

sugar

lemon juice

3 oz. gelatin 3 egg whites well beaten

Freeze the mixture rather slowly. When it is nearly ready to remove from the freezer add the beaten egg whites.

1 For directions for preparing lemon and orange juice see pages 104 and 105.

128

ICE

CREAMS AND ICES
When
the mix-

prevent the fruit acid from curdling the milk, mix and
freeze all the ingredients except the fruit.

ture

is

partly frozen stir in the fruit and complete the

freezing process.
flavor

This gives a sherbet of

and of

finer texture than those

much richer made with water.

Lemon

Sherbet (Milk)
five gallons)

(For about

3 gals, milk 10 lbs. sugar
3 pts.
1

lemon
I

juice

pt.

orange juice
doz. eggs

Whites of

2 oz. gelatin (if desired)

Grape Sherbet (Milk)
3 gals, milk

lo

lbs.

sugar

2 qts. grape juice
1 pt. lemon juice Whites of I doz. eggs

2

oz. gelatin

(if

desired)

Fruit Granite
I
I I

pineapple
doz. bananas
doz.

lemons

3^ doz. ripe peaches Yi doz. apples
I

doz. oranges

WATER
6

ICES
lbs.

AND SHERBETS

129

sugar

water 3 2 oz. seeded raisins 2 oz. blanched nuts
qts.

Spice, if desired

Pare the pineapple and pick
small even sized pieces.
the

it

into bits

;

cut the berries into

Carefully remove the pulp from

the oranges, rejecting the coarser part and the seeds.

Peel

lemons carefully before squeezing them. Cook the sugar and water to a clear syrup. Cool the syrup, pour it into the fruit mixture and freeze it at once. When the mixture is partly frozen remove the dasher, pack smoothly

and allow

it

to freeze

up without further

agitation.

This formula
strawberries

may

be modified to suit conditions.

For

example, the peaches, raisins and nuts

may

be omitted, or

may

be substituted either for the peaches or

for the pineapple.

The

characteristic texture of granites

is

rough and granular. Punch. A characteristic punch is a sherbet to which some kind of spirits have been added, but mixtures containing several kinds of fruit juice highly flavored and spiced are
also

known

as punches.

Roman Punch
(For about
3 gals, water

I

five gallons)

8
J4
1

to 10 lbs. sugar
pt.

lemon

juice

5 qts. fruit juice
qt.

rum

2 oz. gelatin

130

ICE

CREAMS AND
also.

ICES
The
follow-

Mix this and
ing
is

freeze as for sherbets and ices.

sometimes used

Roman Punch
(For about

II

five gallons)

3 gals, water

lo

lbs.

sugar

2 doz. oranges 2 doz. lemons 2 oz. gelatin
1

qt.

liquor

Ordinary punches do not contain liquor but consist of a mixture of fruit juices seasoned with spices of various kinds according to taste.
Fruit

Punch
five gallons)

(For about

3 gals, water

lo 2

lbs.

sugar

qts.

orange juice

2 qts. pineapple juice
1

pt.

lemon juice

2 oz. gelatin
Spices to taste

The spices used in this formula may consist of cloves, cinnamon, nutmeg or any other spices to suit the taste. The mixing and freezing is practically the same as for sherbets.

WATER

ICES

AND SHERBETS

131

Lac to
Lacto
is

a milk sherbet

made from sour

milk, buttermilk,

or fermented milk.
bulletin

A

description of this
first

product with
published in

formulas and direction for making were

form

in

January, 191 1, by the Iowa station.
is

The

following extract
original bulletin
140.

taken from a revised edition of the
published by that station as Bulletin

now

Origin. "When the writer (Professor Mortensen) undertook to overcome popular dislike for sour milk he experimented in flavoring sour milk drinks with fruit juices. At one time such products were placed upon the market, but

on account of the lack of time for advertising no great demand for them was created. " Preparation of milk used for manufacture of lacto. The milk for lacto is prepared in a similar manner to the starter which is used for cream ripening. A commercial lactic acid culture is used. This is added to a pint of skimmed milk which has been pasteurized at a temperature of 185" F. for 20 minutes, and after pasteurization, cooled The lactic acid culture is mixed to from 68° to 72" F. thoroughly with the milk and left at 68° F. until the milk has coagulated. Then another bottle of skimmed milk is pasteurized and cooled in the same manner but instead of a culture, a part of the coagulated milk is added to insure
;

the souring of the milk inside of 18 hours.
is

This operation

repeated until the final batch of soured milk obtained has

due to the substance in which the commercial culture was preserved. After this point has been reached, which requires from four to six days, the last sample of soured milk obtained is added to a larger amount
lost the undesirable flavor

:

132

ICE

CREAMS AND

ICES

This is then treated the of pasteurized skimmed milk. same as the former lots. In this way an amount of milk sufficient to work with is obtained. " Where lacto is to be made in the household on a small scale it may prove too expensive to buy commercial lactic cultures. A family recipe then would be as follows " Take a bottle of good, clean, fresh milk which has not been heated, set it away at a temperature of from 68° to
70° F. until
solid
it

coagulates.

If

it

coagulates as a smooth,

pleasant,

aroma is clean and and the flavor nice and creamy, it can be used as a starter for a larger amount of pasteurized whole or
curd without pin holes,
if

the

skimmed milk. " The milk when ready
acidity of 0.7 to 0.8 of
lactic acid.
It
i

to be used

for

lacto has

an

per cent, expressed in terms of
flavor.

must be of a mild and clean acid

The

curd must be thoroughly broken up. This is accomplished by pouring it from one pail to another until it is as smooth

and velvety as rich cream.
connection will be called
prepared.
"
'

From

this milk,

which

in this

lacto milk,' the various lactos are

Preparing the mixture.

The sugar

is first

dissolved in

the lacto milk.

The eggs

are then prepared.

The whites

and yolks are kept in separate containers and each lot is beaten with an egg beater. Both the yolks and whites are then added to the milk. The mixture is thoroughly stirred and strained through a fine wire gauze. The fruit juices are added last. The freezer is now run until it turns with
difficulty, when moved and the

the paddle

is

removed.

The

brine

is

re-

freezer repacked with ice and salt and left

for an hour before the contents are served. " In the previous report, bacteriological analyses of lacto

WATER

ICES

AND SHERBETS

133
lactic

were published which showed that large numbers of the

acid producing bacteria survive the freezing process.

A

decrease in their number begins, however, soon after this and
continues slowly until eventually but few of these organisms
are living.

There

is

apparently no change in the amount

of contained acid during the storage of lacto."

Pineapple Lacto

(For about

five gallons)

3 gals, lacto milk

9

lbs.

sugar

12 eggs

i/^ gals, grated pineapple 154 pts. lemon juice

Raspberry Lacto
3 gals, lacto milk

9
I

lbs.

sugar
red raspberry juice or concentrated syrup

12 eggs
qt.

ij4 pts. lemon juice

Other lactos such as grape, cherry, lemon, orange,

etc.,

may be made by
above fomiula.

substituting the proper fruit juice in the

CHAPTER
FANCY JIOLDEn

XII
CREAMS

ICE

Ice cream belonging to the class known as the fancy molded ice creams, differs from plain bulk ice cream chiefly In some cases in the form in which it is put up for market.
there

may

be a slight difference in formula but the principal
is

difference

in the

manner

of coloring and in the size and

form of package.

The
of a
of

difference in formula consists usually in the addition

more of some kind of stabilizer or the addition more milk solids to obtain a better body. The difference in package is one of the distinguishing The most common package features of fancy ice creams. or form of molded ice cream is the quart brick. Considerable ice cream is molded in the form of some object, such as an animal or a statue and may contain a number of quarts of ice cream. The individual pieces are also molded in imitation of some object but of such size that each piece
little

contains enough ice cream to serve one person.

For a
cream up
in
is

different class of trade.

intended

for a

products are for the
gallon packers.

The fancy molded ice The plain bulk ordinary retail trade and are made
special

trade.

standard flavors and packed in the large

five to ten

The fancy molded
134

ice

creams, on the other
balls,

hand, are for special occasions such as parties,

ban-

FANCY MOLDED
quets,

ICE

CREAMS

135

and similar entertainments. The quantity in which any one kind of molded ice cream may be made will depend upon local conditions. In the larger cities there is always a demand for plain bricks of ice cream or for bricks containing two or more flavors and colors. These are usually made up in quite large quantities daily. There is sure to be a demand also for special forms, flavors and colors of ice cream for special functions.

Fig.

32.

Cutting and

wrapping brick ice cream Creamery Co.

in

the

Hendler

By timely suggestions and careful advertising, the wide awake and progressive ice cream manufacturer will endeavor Sucto stimulate a demand for special kinds of ice cream. cess in this line requires no small amount of ingenuity,
originality

and an

artistic taste.

Original ideas and designs will always

command

a pre-

136

ICE

CREAMS AND
is

ICES
ice

person

mium where there who wishes

any market for fancy

creams.

A

welcome any suggestions in regard to appropriate form or flavor of the ice cream or ice to be served and will be willing to pay a special price The for something new and appropriate for the occasion. ice cream maker who can give these little suggestions is sure of success, but it requires the exercise of good taste to
to entertain will

do

so.

Harmony
The
colors

of color

and flavor

is

of great importance.

and flavors should be selected with much care. That is to say, the color must be suggestive and must harmonize with the flavor. For example, a vanilla ice cream is always white, but a strawberry ice cream is pink because that is the color naturally imparted by the fresh fruits. Preserved fruits do not color the mix sufficiently, so it is customary to add pink coloring matter. It would most certainly be a bad combination of colors and flavors if one were to color a vanilla ice cream pink or a strawberry ice cream brown. Not that coloring adds or detracts from the flavor, but unless the two harmonize, there is nothing
suggestive in the color.

Coloring matter should be used sparingly.
should not be too deep, for in that case there
of artificiality
is

The

colors

a suggestion

and cheapness. Light and dainty tints are and pleasing to the eye. The amount of color used in any case is small, but it must be free from odor or flavor and absolutely harmless. The color is one
the

most

attractive

of the important features of fancy ice creams.
sired shade

Any

de-

may

be obtained by blending various colors.
in the proper

For example, yellow and blue when mixed
proportions give a green color; red and blue

make purple;

yellow and white

make

a cream color; pale blue and red

FANCY MOLDED
give a violet tint
;

ICE

CREAMS

137

pale red and white give a very dainty pink. must not only harmonize with the flavors, but where two or more colors are used in the same mold they should harmonize with one another. Layer bricks are made in the ordinary brick molds but contain two or more kinds of ice cream in uniform layers. The different layers should be of uniform thickness and clearly defined. These bricks when carefully made and in colors and flavors that harmonize are very pleasing in ap-

The

colors

tx*^^
Fig. 33.

A

Three-layer Brick.

pearance.

Striking contrasts in color, as a rule, are not

pleasing, but there

may

be occasions

when

fantastic colors

are permissible or even desirable, as for example,
is

when

it

necessary to match some general color scheme for a

special occasion.

Special designs also
colored field

require

special

colors.

A

heart

center, for example, should be pink in a white or cream
;

a shamrock should be colored a light green in
ice

a white or very pale green field. Individual pieces and the large molded forms of

cream should be colored to correspond with the objects they represent. The same precaution should be observed

138

ICE

CREAMS AND ICES

kind and amount of color to use and the cream in these special forms. Brick molds. The most common form of molded ice cream is that which is put up in bricks. These are usually of one quart capacity and measure 2%x3'4x6^ inches, but there are other molds of different capacities and different dimensions. For example, the four and eight quart sizes, known as sectional molds are about 63/4 inches wide, 2^ inches deep, and I2.)4 or 25^ inches long. Sectional molds ars used in making up ordinary quart
in regard to the

flavor of the ice

bricks in large quantities.

The width

of these equals the

length

of

the

ordinary quart bricks.
is

Extending across

the bottom of the mold

an indentation every 314 inches.

Foot Lever

Fig. 34.

Hauk's Brick Cutter.

For cutting sectional bricks into one quart bricks.

These indentations mark the places where the large brick must be cut to make up quart bricks. The sectional molds are usually of the single lid type, but the one and two quart molds may be obtained in either single or double lid

FANCY MOLDED
type.

ICE

CREAMS

139

molds have a number of advantages The principal advantage is the facility with which the frozen cream can be removed from the molds. The single lid molds, however, are tight at the bottom and there is therefore less danger of brine getting into the mold and spoiling the ice cream. The molds should be made of quite heavy material and should be well tinned so that they may be kept clean and bright. The lids should fit well, but it will always be necessary to place parchment paper under the covers to prevent the brine from working in.
lid

The double

over the single

lid

molds.

Fancy center bricks may be made in structed brick mold or the centers may be
in

a specially con-

frozen separately

a special mold and afterward inserted in the ice cream in

a plain brick mold.

In the special fancy center molds the outer portion or background is frozen first. The mold in which the freezing The outer part is the size of an is done is in two parts. ordinary quart brick and is provided with lids at the ends Attached to one of the lids and instead of top and bottom. running lengthwise through the mold is the second or inner part which is made in the shape of the desired central design. To use these molds one lid is made tight with parchment paper and the mold filled to within one and a half
inches of the top with soft ice cream.
thrust
is

The

center piece

is
it

down

into the ice

cream

until the

cover to which

attached comes into place.

The cover keeps
is

the center

piece exactly centered.

The mold The

then packed

away

to

freeze, but should be kept in
ice

an upright position
center piece
it

until the

cream

is

well hardened.

is

hollow, so
of¥ the ice

that cold water can be poured into

to

thaw

cream.

The

center piece

is

then removed, leaving a hole

140

ICE CREAiAlS

AND

ICES

Fig. 3S-

Showing some of the Fancy Center Designs
cream.

for brick' ice

FANCY MOLDED

ICE

CREAMS

141

through the brick just the shape of the desired center design. The space is then filled with ice cream or sherbet of some other color and a plain lid put on the mold which is again packed away until the ice cream in the center is thoroughly hardened.

Fig. 36.

Showing
is

a

few of the different types of Ice Cream JMolds.

There
center
is

frozen

another type of fancy center mold in which the first in a separate mold and is afterward im-

bedded
are

in soft ice

cream

in the

ordinary quart molds.

These
of de-

known

as Cassell fancy centers.

Cassell fancy center molds consist of a
tachable sections which

number

be taken apart to remove the molded object or center without marring or thawing the ice cream. The great advantage of molds of this type is that the ordinary quart and sectional mold may be used for freezThe cost of the molds ing the outer portion of the brick.
is

may

therefore greatly reduced.

Another advantage

is

that

the mold comes apart so that more, complicated designs

may

142

ICE CREA^IS
It is

AND

ICES
the center

be frozen.

somewhat more

difficult to get

pieces properly centered in the mold, but when one becomes accustomed to this type of mold, very neat and rapid work

may

be done.

Fancy center bricks are made by this method by first "freezing up" the desired- number of centers. These should be kept in the hardening room until they are to be put into the bricks. A sectional mold is then filled about half
full of

fresh ice cream.
just

The frozen
far

centers are laid in the

mold crosswise and
the large brick contain
is

enough apart so that when
the
center pieces

cut up into quarts each quart brick will

a center piece.

When

are

in

place the

mold is finished by filling with the soft ice cream. The filled mold is then frozen in the same way as any other Practically all brick ice cream is put out in the one brick. quart size, but ice cream which is molded in special molds in the form of some object may contain anywhere from onetenth of a quart to several quarts of ice cream.

Individual molds are of such size that each mold will
hold just enough ice cream to serve one person.

These

Fig- 37-

Individual Molds.

FANCY MOLDED

ICE

CREAMS
for
festive

143
occasions

individual pieces are very popular

where some appropriate form can be selected. The method of preparing these various kinds of molded
ice

cream, although apparently very simple, requires

much

practice and patience to turn

them out rapidly and neatly. The molds should be clean and well chilled before the ice cream is placed in them. Each half of the mold is then filled with ice cream and the mold pressed together tightly and packed away to freeze. The ice cream which is put up in these various molds
does
ice
tial,

not

always
It is

differ

in

composition from plain bulk

cream.

very essen-

ice

however, that the molded cream should retain its

the mold.

form and the impression of Under some cirit is

cumstances

advisable to

make up
ice

a special batch of

cream having a heavier body for the molded ice cream ice cream. The
should not be very firm

when
Fig.
38.

molded.
it is

For brick ice cream
mold
it

Hauk's
filler

Mold
is

Filler.

best to
it

as soon

after

is

taken from the

freezer as conditions will permit.
ier
ice

In addition to the heavloss

attached to the delivery spout of the freezer and the molds filled directly from the machine without further handling or transferring.

The mold

in

handling a firm
it

cream,
is

is

also

There

a device

more difficult to fill a mold properly. on the market now which can be attached

144

ICE

CREAMS AND ICES
one to
fill

to the delivery spout of the freezer to enable

brick molds

directly

eliminate the loss

from the freezer and in this way of time and of ice cream incident to

handling a second time.
ice

What

has been said regarding
to sherbets

cream for molding, applies also

frequently used in connection with ice cream for

which are making

fancy bricks.

Sherbets and ice cream.
sherbet and one or
lar.

Bricks containing a layer of

more

layers of ice

cream are very popu-

The molds
it

are prepared the same as for ice cream,
will require a

but as a rule

lower temperature to freeze

the brick up properly.

A

brick containing one layer of

sherbet or ice and two layers of ice cream is best made up by placing the layer of sherbet between the two layers of ice cream, particularly if there is likely to be any difficulty in keeping the brick 'well refrigerated before it reaches the

consumer.

A
ice

little

practice will soon enable one to turn out brick
easily

cream

and

rapidly.

The
is

difficulties

most

fre-

quently encountered in making brick ice cream, especially
in small factories

where the freezing

done

in

a mixture of

ice

and

salt,

are insufficient freezing and the presence of

cream. These difficulties may be overcome by proper packing and proper preparation of the molds in
salt in the ice

which the ice cream is frozen. Preparation of molds. Ordinarily a brick mold is prepared by making the covers tight with several layers of parchment paper. This is sufficient preparation where the molds do not stand in brine. If, for any reason, it is necessary to freeze the ice cream very quickly, the seams of the mold can be made tight by pasting a strip of buttered paper over them. A part of the brine can then remain on

FANCY MOLDED
the

ICE

CREAMS
rapid.

145

freezing mixture without danger of spoihng the ice

cream, and the freezing will be

much more

Freezing molded ice cream. In the factories which are equipped with a dry air hardening system the manufacture of molded ice cream is' greatly simplified. In most small factories, and in many large ones too, the bricks and other forms are still frozen in a mixture of ice and salt. The ice

Fig.

39.

Mono-service

Ice

Cream
salt

Container.

should be crushed quite fine and

added

in the propor-

tion of about one part salt to five or six parts of ice.

The

which the molds are packed must be so arranged that the brine can drain away. The object of allowing the brine to drain off is to minimize the possibilities of any of the brine getting under the covers and spoiling the ice cream. Removing the ice cream. It is not a very difficult matter to remove the ice cream from the mold, provided it has
in

box

146

ICE

CREAMS AND

ICES

Fig.

40.

Section througii

a J\Iono-service

container,
ice.

showing

in-

sulation and space for

Fig. 41.

Section through Week's Carrier.

FANCY MOLDED
been well frozen.
the ice cream

ICE

CREAMS
may be

147

The

larger molds

dipped into

cold water once or twice, which will be sufficient to thaw

from the

side of the

mold without softening
Small molds, such

more than

the very outside of the brick.

as the individuals, and centers for the fancy center bricks,

may

be exposed to room temperature for a

moment
all

or two

or simply wiped with a wet towel to loosen the ice cream

from the mold.
avoided.

Much thawing must by

means be
from

Packing for market.

When

the bricks are removed

the mold they should be wrapped in

waxed papers and placed This work should be done in a special room in in cartons. which the temperature can be kept moderately low. The
into

bricks are packed in brick tank packers which are square and

which the bricks

will

fit

nicely.

Special packing cans,

containing a series of

removable shelves, must be used for individual pieces and other special forms to prevent injuring the impression on the molded ice cream in transit.

CHAPTER

XIII

THE FREEZING PROCESS
The
into
is

freezing process may, for convenience, be divided
parts.

two

In the
it

first

part of the process, the

mix

agitated while
it is

is

freezing.

When

frozen to a certain

consistency,

transferred to a packing can and the freez-

ing or hardening completed without agitation.
tity

The quan-

and quality of

ice

cream obtained

will

depend upon the

proper manipulation of temperature and the speed of the
dasher in the freezer.
in the ice

In the freezer. That part of the processs which is done cream freezer has for its object the lowering of

the temperature in such a

way
it

that ice crystals will not

becomes hard. This is accomplished by agitating or beating the cream vigorously
in the ice

form

cream after
is

while the temperature
agitation
is

being reduced.

The

result of this
air in

the incorporation of a certain

the mix. ing point

The
is

increased viscosity

amount of of the cream at the

freez-

sufficient to

prevent the escape of the air; con-

cream mixture increases in volume 50 to 100 per cent. This increase is spoken of as the siuell and is essential to good quality in the ice cream. The mix should be frozen just hard enough to retain this swell. No attempt should be made to carry the freezing any farther
sequently, the ice

than this in the freezer, because the agitation,
148

if

continued

THE FREEZING PROCESS

149

very long after the ice cream has reached the freezing point, will cause it to beat down, resulting in a loss both in
quantity and quality.

The purpose
the freezer
sistency
is

of the freezing process as carried out in

cream up to a light creamy conand reduce the temperature to a point where the
to beat the

A
viscosity will be great

North Freezer.

enough to retain the swell obtained When ready to remove from the freezer, the ice cream should be viscous enough to retain the swell but thin enough so that it may be poured from one The rapidity with which the mix is vessel to another. frozen will therefore have a great influence upon the quanin the freezing process.

I50
tity

ICE CREAAIS

AND

ICES

batch.

and quality of the ice cream obtained from a given According to Washburn, the maximum swell is obtained when the mix has been cooled to a temperature of
Transferring.

28° F. or 29° F. in ten to fourteen minutes.

When
it

the cream has been frozen to the

proper consistency
tion.

should be transferred at once to pack-

ing cans and the freezing process completed without agita-

The

ice

to expel the air

agitation in

cream should be handled carefully, so as not which has been incorporated during the the freezer. It is for this reason that ice cream

% Swell

B-

10;

38;

36:

s+i

se'-i",

3i;3o;e'i;£i;2i;es;e8;E7;eT,'E&;e6°£5;E5?r

Fig. 43.

Chart showing the effect of temperature on the swell of ice cream. The figures below line represent the temperature of the mix taken at intervals of one minute. BB represents the space occupied by the mix, before, during and after freezing.

AA

(From

Bulletin 155,

Vermont Agricultural Experiment

Station.)

should be in a soft condition

when

transferred.

The

ice

cream should not be transferred from one receptacle to another any oftener than is necessary. The packing cans should be chilled before the ice cream is placed in them so that the first ice cream will not be melted by coming in contact with the warm can. The chilling may be done by placing the can in a mixture of ice and salt in a packer, by placing them in the hardening room

THE FREEZING PROCESS
room may be
refrigerated to l^eep
it

151

for a short time before they are used, or the can storage
tlie

cans cool.

Where such

be found highly satisfactory, because the room may be kept free of flies and the cans are always in condition for immediate use and may be
a system can be installed
will

taken from the store room as needed.
cover.

As

the cans are

filled,

a piece of parchment paper should be placed under the

The

cans of ice cream are then packed in ice or

placed in a brine tank or hardening

room

to freeze.

Hardening. The final freezing, which is done after the cream is removed from the freezer, is known as the hardening process and may be accomplished in several ways. The final result is the same in all cases, but the method adopted will be governed largely by the capacity of the plant and
the

amount

of capital to be invested in a hardening system.
is

A

slush box

generally used in the small plants for

hardening the ice cream. Where this system is used the cans of ice cream are packed in a mixture of ice and salt to
harden.

The

slush

box

is

simply a large water-tight box,
insulated to insure

usually of wood. greater efficiency.

The box should be
hardening system
is

The dry
favor.

air

rapidly

gaining in

In the larger factories, and in

many

of the smaller

ones also, this system has replaced the others which have been mentioned. In this system the air In a well insulated room is kept at a very low temperature by means of expansion coils, and the ice cream is frozen in perfectly dry

This is unquestionably the cleanest and most method of hardening, but as has been pointed out, the advantages and disadvantages are largely matters of economic efficiency rather than effects upon the quality of
surroundings.
satisfactory

152

ICE

CREAMS AND

ICES

the finished product so far as texture and swell are con-

The control of texture and swell depends largely upon the proper control of temperatures and agitation in
cerned.

the freezer.

The time required for proper freezing will be governed by several factors. In the first place, the different kinds of mixtures to be frozen will affect the time somewhat. For example, sherbets and ices require more time and a somewhat lower temperature than ice creams, but if the sherbet is to be sold as a granite, the freezing must be done more rapidly and with less agitation because rapid freezing and little agitation are the conditions that give the rough texture characteristic of granites. If it is to be sold as frapf>c, however, it must not be frozen so quickly and must be agitated vigorously while in the freezer to produce a smooth and uniform texture. The time required for freezing ice cream mixtures will depend somewhat upon the composition, but more upon the temperature of the mix when put into the freezer. The temperature of the mix. It has been pointed out that cream should be held in storage at a very low temperature for the purpose of inhibiting bacterial growth. There is another reason for this, however, and that is to rif'cn l'>y ripening, as applied to cream for ice cream the cream. making, is meant tlie processs of cooling, and holding, particularly after pasteurization, to restore the body and visIf for any reason it is necessary to cosity to the cream. the cream or to cook the mix, great care must be scald
taken to cool
it

thoroughly before
is

it is

placed in the freezer.

Thorough cooling
churning

essciUial not only to reduce the time

required for freezing, but to reduce the danger of the cream
in the freezer

and

to secure a better swell.

The

THE FREEZING PROCESS
from about 10 to 14 minutes.^ Rapid freezing. If the freezing is carried on the mix is not subjected to sufficient agitation
will be

153

time required for proper freezing, under normal conditions,

too rapidly,
to secure a

good

swell, because the
is

temperature drops so quickly that

the freezing point

reached before the

maximum

swell has

been obtained.

In addition to the loss of swell, too rapid
in

freezing does not produce ice cream of the best texture.

Granular texture
freezing.

is,

many

instances,

due

to too rapid

The production
amount

of a smooth and pleasing texture of agitation during the
first

requires a certain

part

of the freezing.
tion,
salt to freeze

To

illustrate the necessity of

proper agitait

take a small quantity of the

mix and pack
It will

in ice

and

without agitation.

be found that the
is

increase in

volume due

to freezing is

very insignificant and

that the texture, instead of being smooth and velvety,

coarse and granular.

Prolonged freezing, on the other hand, may also
a loss of swell, but from a different cause.

result in
it

In this case

would be due
the

to the fact that the agitation, if carried

on

aftfer

maximum
to beat

swell has been obtained, will cause the ice

cream

down;

that

agitation will break the
in the ice

is, it will become so stiff that the cream and allow the air incorporated

cream to escape.
this,

the prolonged agitation may cause Should this happen, small granules of butter will be found distributed through the ice cream, or the ice cream may have a greasy body. This difficulty is frequently encountered in freezing a mixture containing a high percentage of fat, particularly if the mix has not been

In addition to

the cream to churn.

properly chilled.
1

Bulletin 155,

Vermont

station.

154

U'l'.

CRI'AMS AXl)
iiKclianical

iri'S
tlic

Low
must he

speed.

Hir

part nl

process must
of the ihisluT

also be taken into coiisiilcralion.
siillicicnt

'ilic spei'il

to !;i\e '^inn\ aj^ilatioii.

If the a,i;itatioii

I'ig.

.14.

A

I'liitjn'^s

I'uc/cr with

liriiic

Imx

aiul ciiciiliiting

piiiiiii.

is

not

vit^'oroiis

enough the
tiie

coohiiL;' will

not he so

uniform

thronL;iu)Ht

nor

will the swell

he so

lar,L;e.

Too high

speed, on

other hand, will ha\e an elTeet
;

similar to that prodneed by loo proh.jnged free/ini;

nainclv.

THE FREEZING PROCESS
loss of swell

155

due to beating down and churning, or produc-

tion of a greasy body.

The

control of the various conditions which

may

affect

the proper freezing must be left largely to the judgment

and close observation of the ice cream maker, but the means of control will depend to a very considerable extent upon the kind of freezer used. Types of ice cream freezers. There are various types of ice cream freezers in use in the factories, the oldest type
being the upright tub freezer in which the ice cream is frozen by packing ice and salt around the can, the mixture

^m

156

ICE

CREAMS AND
of ice

ICES
In the ordinary tub

The proportion
is

and

salt.

freezer the rate at which a given batch of cream will freeze

regulated to a very considerable extent by the proportions

of ice and salt used.

The very low temperature obtained and ice is due to the fact that when a substance changes from a solid to a liquid form it must absorb
by mixing
salt

a certain amount of heat.

With

ice, this

process of lique-

Fig. 46.

The New Rapid

Ice Breaker,

showing the arrangement of

crusher teeth.

faction

is

hastened by the addition of

salt,

resulting in a

very sudden absorption of heat from the substances near The temperature reached will the ice and salt mixture.
therefore depend upon

how

rapidly the ice melts, and

may

be governed to suit conditions by altering the proportions of ice and salt and to a certain extent by the size of the ice

THE FREEZING PROCESS
particles.

157

Under most conditions a mixture of one part of salt to ten or eleven parts of ice will be sufficient, but if the mix is very cold the proportion of salt should be
reduced to avoid too rapid freezing.
will be of fairly

should be crushed in such a way that the pieces uniform size, small enough to pack well in the tub. Large chunks not only do not pack well and leave large air spaces, but melt too slowly. This fact should be kept in mind, because it is sometimes necessary to produce a very low temperature, in which case the ice must be finely crushed and more salt used. Thi^ holds true whether the ice and salt mixture is packed around the freezing can or made in a separate container and the cold brine which runs from the melting ice used as the freezing
ice

The

agent.

Brine freezing has many advantages over the old method. first place, it is possible to keep the floor cleaner around the freezer, because a new charge of ice and salt may be added to the brine at any time without interfering with operations in any way. Furthermore, the cold brine comes in contact with all parts of the freezing can, resulting Probably the greatest advantage is in in greater efficiency. the more perfect control over the freezing by regulating the temperature and rate of flow of the brine. This method of freezing may be employed with the ordinary tub freezer by providing a tank in which the cold brine may be made. A rotary pump must also be provided to circulate the cold brine around the freezing can. With this system of brine freezing the temperature of the brine is regulated by the proportion of ice and salt in the mixture. The temperature of brine cooled by mechanical means.
In the

IS8

ICE

CREAMS AND

ICES

THE FREEZING PROCESS
however,
to
is

159

regulated by the

expand

in coils of pipe
is

amount of ammonia gas allowed submerged in the brine. Where

the brine

cooled in this

way

the temperature

may

be

regulated more accurately and as a result the freezing process
will

be under more complete control.

CHAPTER XIV
REFRIGERATION
Ice

ural ice

cream making is largely a refrigeration process. Natwas originally used as the refrigerating agent, but
it

mechanical refrigeration has developed so rapidly in recent
years that
its

has been adopted by

many

greater efficiency and cleanliness.
is

factories because of Mechanical refrigera-

tion

no longer confined to large plants exclusively. In use in ice cream factories is becoming so general that a book of this sort would hardly be complete without a brief discussion of this process and its application to ice cream making. Refrigeration is an interchange of heat between substances of different temperature. This interchange of heat may be accomplished in various ways, but the process is
fact
its

known

as refrigeration regardless of the

means employed.

Natural ice was originally the only refrigerating agent that could be put into general use. The unit for measuring refrigeration is therefore based upon the refrigerating capacity of
ice.

When we speak
we
simply

of so

many

tons of refrigerat-

ing capacity

mean

the equivalent of so

many

tons

of ice melting in 24 hours.

The

British thermal unit.

Just what

is

meant by

a ton

of refrigeration will be better understood by determining the actual absorbing capacity of a ton of

measured by what

is

known

as the British

ice. Heat is Thermal Unit

160

REFRIGERATION

i5i

:

i62
(B. T. U.).

ICE

CRKAMS AND

ICES
is

A

British

Thermal Unit

the

amount of

heat required to raise the temperature of one pound of

water through i" F. of temperature, or the amount of heat that must be withdrawn from one pound of water to lower
its

temperature i" F.
142
T. U.

To
it

convert a pound of water at
will

32" F. into ice at 32° F.,
it
I).

liquid state

A

ton of

be necessary to take from pound of ice can pass into a again it must take up 142 B. T. U. refrigeration represents the amount of heat ab-

Before

this

sorbed by 2000 pounds of ice at

32^'

F. in melting into 2000

pounds of water
sensible

at ;i2"

F., or 284,000 B. T. U.

Kinds of and

heat.
latent.

Heat may be
Sensible heat

said to be of
is

that

two kinds which may be felt
Latent

or

may
is

be determined by means of a thermometer.
temperature.

heat

the heat required to change the state of a substance
its

without increasing
its

For example,

if

we

take a pound of ice and, by means of a thermometer, find

temperature to be

;^2

degrees, that would be 32 degrees

of sensible heat.
at 32 degrees,
it

If this ice

be allowed to melt into water

B. T. U.
ice,

it with 142 Since the water has the same temperature as the

will be

necessary to supply

the heat required for liquefaction can not be measit

ured with a thermometer although

has been taken

the ice in passing into a liquid state.

vtp by These 142 heat units

are therefore called the latent heat of liquefaction of ice. Latent heat of liquefaction is made use of when salt

is

mixed with
an
affinity

ice in the freezing process.

The

salt

has such

for water that
ice, in

it

causes the ice to melt
its

more

rapidly.

The

order to change
its

form, absorbs the

necessary heat from
rapid liquefaction
is

surroundings.

The

result of the

a sudden lowering of the temperature.

Endothermal

actions.

Other substances than

ice

and

REFRIGERATION
salt

163

may

be used for the production of low temperatures.

temperatures.

when mixed will produce low Chemical changes in connection with which heat is absorbed are known as endotherinal actions. This method is not used in practical refrigeration, however, on account of the cost of the necessary chemicals.
Certain chemical substances

Compressed
ing agent.

air

was

" In this

also used at one time as a refrigeratdevelopment inventors in Australia took

a leading part, being stimulated by the

demand

for a process

for preserving, in a fresh condition, the cheap

that country until landed on the shores of England.

mutton of For

use on shipboard, compressed air machines were originally

employed, but they are

now going

out of use, having been

supplanted by simpler machines which can be operated more
economically.'' ^ Quite low temperatures may be produced by compressing and cooling air and then allowing it to expand in the area to be cooled. These machines, however, require too much power to a ton of refrigeration and are therefore less satisfactory and less economical than those machines which use some other gas, such as sulphur-dioxide, carbon-dioxide, or ammonia. The process of producing low temperatures by the use of any of these substances, with the aid of the necessary mechanical appliances, is spoken of as
artificial refrigeration

or mechanical refrigeration.

Mechanical refrigeration is a comparatively recent development, and it is only within the last few years that this process has been used to any extent in the ice cream indusOn account of the greater efficiency and for sanitary try.
reasons, mechanical refrigeration
is

rapidly gaining in favor

among ice cream manufacturers. Of the various gaseous substances which may be em1

Bulletin in,

West Virginia

station.

164

ICE

CREAMS AND
principle

ICES

ployed in mechanical refrigeration, ammonia
generally used.

is the one most upon which all of these machines operate is the same whether the refrigerating agent be carbon-dioxide, sulphur-dioxide, or ammonia. The difference in the chemical and physical properties of these substances, however, may necessitate some slight difSince amferences in the construction of the machinery. monia is the most common refrigerating agent used in

The

Fig. 49.

A

Vilter Compressor.

mechanical refrigeration, this brief discussion will be limited
to

ammonia machines.

Ammonia
The pure

is

obtained commercially from sal-ammoniac.

liquid

ammonia

is

a colorless fluid with a very pun-

gent odor and an alkali reaction.

The

liquid

ammonia,

at

atmospheric pressure, boils at a temperature of 28.5 degrees below zero Fahrenheit. It is, therefore, a gas under ordi-

nary conditions.

A

cubic foot of the liquid weighs 39.73

REFRIGERATION
pounds.
liquefy,
Its

165
is

value as a refrigerating agent

due to the low
it

pressure and comparatively high temperature at which

will

in

making it easy to condense the gas to a liquid form. There are two methods by which ammonia may be used refrigeration. One is known as the absorption method

Fig. 50.

A

Remington Compressor.

gas, instead of being

In the former the compressed by mechanical means, is obtained from a solution of ammonia in water which is heated in a still to drive off the ammonia gas, which is later condensed. The ammonia then passes through the expanIn the absorber the sion valve and back to the absorber.

and the other

is

the compression system.

1

66
is

ICE

CREAMS AND

ICES

gas

brought into contact with the water, called the mother from which it was originally extracted, the water in the meantime having gone through a cooling process. The cool mother liquid rapidly absorbs the gas and forms a strong solution of ammonia, which is returned to the still
liquid,

by means of a pump and

is

again ready to go through the

Fig.

51.

A

York Compressor. This system has been abandoned
is

same

cycle of operations.

almost entirely in favor of the compression system.

The compression system
alternately compressed

so

named because

the gas

is

by mechanical means and then expanded. There are three distinct operations in the compression system viz., compression, condensation, and ex;

pansion.

The gas

is

compressed by means of a compressor to a

pressure varying from 125 to 175 pounds to the square inch.

REFRIGERATION
In this compressed condition the gas
water, which causes
liquid
it li
;

167

cooled by means of

to

condense

it

then collects in a

form

in a receiver.

The

liquid

is

piped from the re-

ceiver to the expansion coils.

In order to reach the expasses into a gaseous state.

pansion

coils the liquid is

allowed to escape through the exit

pansion valve, whereupon

After the gas has expanded
pressure on the condenser
is

it is

pumped back
to 175

to the

comthe

pressor, thus completing the cycle of operations.

As

pounds and the pressure on the expansion coils is only 15 to 20 pounds, it will be seen that the system may be divided into two parts known as the high pressure side and the low pressure side. All that portion of the system from the discharge valve on the compressor to the expansion valve is on the high pressure side, and all from the expansion valve to the induction valve on the compressor is included in the low pressure side
of the system.

from 125

In a refrigerating plant, using the compression system,
the compressor
is

a vital part of the equipment.

The

effi-

ciency and capacity of the plant depends largely upon the

and capacity of the ammonia compressor. The is used to pump the expanded gas from the expansion coils and deliver it to the condenser. Ice cream refrigeration differs from ice making and ordinary cold storage in that the freezing must be accomplished This must be kept in in a few hours instead of days.
efficiency

ammonia compressqr

mind in installing refrigerating machinery. The mistake must not be made of installing a machine of too small cais based upon a where machines are run for less than 24 hours a greater capacity is required. That is, if one ton of refrigeration is required and the machine is to

pacity.

A

ton of refrigerating capacity
so that

24-hour run,

;

i68

ICE

CREAMS AND
it

ICES
two-ton
stroke

be run only 12 hours,

will be necessary to use a

machine.

Requirements of a good ammonia pump.

The

of the piston must be accurately gauged in order that the clearance between the follower and the cylinder head

may

be as small as

is

consistent with safe operation and to inIf there

sure complete expulsioii of the gas at each stroke.
is

much

clearance between the follower and the cylinder

pump will be reduced, because the compressed gas in the space between the follower and the cylinder head will not permit the suction valve to open until the piston has started on the return stroke and allowed the gas to expand until the pressure in the cylinder is below the pressure on the opposite side of the suction valve. The capacity of the compressor depends upon the number of pounds of gas which it can handle in a day consequently, the size of the rooms to be cooled and the temperatures to be maintained must be taken into consideration and a compressor of ample size selected so that the desired temperature may be maintained as economically as poshead, the capacity of the
;

sible.

The

stuffing boxes.

The leakage

of ammonia, even

if

so

slight as to cause but little expense,

is

alwa>s an annoyance.

The most

of the leakage occurs around the stuffing boxes

hence, they must be watched very carefully.

The

stuffing

boxes should be of unusual length, but with whatever care
they are designed, they will require frequent attention
in all

machines to keep the packing
age.

set

up enough

to prevent leak-

The packing must be kept
is

sufficiently

tight to prevent

leakage but not so tight as to cause the box to heat.

This

a point that must be watched constantly.

The

stuffing

refri(;erati()N

169

box should be so designed that the packing may be adjusted' while the machine is in operation. The valves must be of sufficient area to allow a free passage of the gas through them.

They must be durable
struction
tion

in con-

and

reliable in acis

so

that there

little

danger of their getting out
of order.

As

the

ammonia

system must be as free from air as possible, the fewer
times any part of the system
is

opened for repairs the betIn
refrigerating
as
in

ter.

ma-

chinery,

every other

kind of machinery, repairs
will

be needed from time to

time.
loss

To
of

prevent any great
or
the
intro-

gas

duction of air into the system, the compressor should

be

provided

with

bye-pass

valves.

The bye-pass
cross

valves are

simply a system of valves and
connections
suction

between
discharge

the

and

Vertical section through Fig. 52. the Vilter Stuffing Bo.x.

pipes,

so arranged that the
part of the system and

ammonia may be pumped from one
tions are

temporarily stored in another part while repairs or examina-

made.
are special valves located at the top

The purging valves

170

ICE

CREAMS AND
air.

ICES

of the cylinder or on the highest part of the condenser and
are used to free the system of

The

condenser.

From

the

oil

trap

the
is

ammonia gas

passes to the condenser, where the hot gas

cooled to a tem-

perature sufficiently low to cause
ter of condensing

it to condense. If an abundance of cool water can be obtained cheaply, the mat-

is

very simple.

In some of the large

Fig.

S3.

The

Vilter

Atmospheric

Condenser.

plants

where very large compressors are used, the expense
is

of water for cooling

sometimes very great.

Probably

the cheapest and most economical type of condenser to use

under such circumstances is the open air type, which should This for convenience be located on the roof of the building. condenser consists of two parts, the first part being a preliminary cooler which is located below the liquefier. In the
preliminary cooler the gas
is

partly cooled before reaching

REFRIGERATION

171

the liquefier, which consists of a series of coils of pipe.

These are cooled by water which is sprayed over the outside of the coils and drops down into the preliminary cooler. In this way the warmer water comes in contact with the warmest gas, but as the water is much cooler than the gas coming directly from the compressor, it is cooled considerably in the preliminary cooler.

The submerged cooler. In another cooling system the condensing pipes are entirely submerged, the water flowing in at the bottom of the tank and running out at the top.
This
is

but

little

used, as

it

requires
*^
is

too large a volume of water.

^*.

The double

pipe system

now
This

used quite extensively, especially on
the smaller types of machines.

type consists of a series of small
pipes within larger pipes.

The ammonia gas flows through the larger
In this

pipes.

way

it is

exposed

in a

very thin layer to the cold surface of
the small pipe.

The
it

hot gas enters

the coil of pipes at the top and flows

downward
tion.

until

is

condensed and

runs to the receiver in a liquid condi-

The

cooling water enters the

small pipes at the bottom and flows

upward and

is

discharged at the top.

The

oil trap is
oil

used to free the
If but

ammonia from

and other impurities taken up while passone trap
is

ing through the compressor.

used,

it

is

placed in the high pressure side between the discharge valve

and the condenser,

Except

in the very small plants

two

oil

172

ICE

CREAMS AND

ICES

traps are usually placed in the system, the second trap being

located in the low pressure side of the system

between the expansion

The receiver ammonia flows

is

somewhere and the induction valve. a strong iron tank into which the liquid
coils

as

fast as

it

condenses.

The

liquid

am-

Fig. SS.

The

Viltcr Oil

Trap and

Fig.

s6.

The

York

Liquid Receiver.

Expansion Valve.

monia is piped from the receiver to the expansion coils where the actual work of refrigeration is accomplished. The expansion valve. Between the receiver and the expansion coils is a valve known as the expansion valve, which
is

so constructed as to admit of a very fine adjustment.

The

flow of

ammonia

is

controlled by

means of

this valve.

REFRIGERATION
The expansion
the
coils. It is in the
is

173
coils

expansion

that

work of refrigeration liquid ammonia to enter
valve.

accomplished by allowing the the coils through the expansion
is

Since the pressure in the expansion coils

quite

low, the liquid

ammonia changes

into a gaseous condition

very rapidly after

it passes the expansion valve. This change from a liquid to a gaseous condition entails the absorption of a certain amount of heat from the surroundings and results in a rapid lowering of the temperature in the vicinity of the expansion coils. The refrigeration produced by the expansion of ammonia may be utilized either by the brine system or by direct expansion. In the brine system the expansion coils are submerged in a tank of brine. After being cooled the brine is pumped through pipes in the cooling room, to the brine freezers in the ice cream factory, or cans of water may be placed in the tanks of cold brine and frozen into ice. In the direct expansion system the gas is allowed to expand in This system is used coils placed in the room to be cooled. where very low temperatures are desired. The brine and direct expansion systems. There are advantages in both systems hence, the one to use will depend upon local conditions. For hardening rooms the direct expansion system must be used, but as the work of refrigeration ceases as soon as the compressor stops, it will be necessary to operate continuously. Where the compressor is to be run intermittently, the brine system has some advantages over the direct expansion system, as a large body of brine can be cooled in a comparatively short time, the compressor stopped, and the store room kept cool by circulating the cold This system is well adapted to cooling rooms which brine. rnust be kept at a moderately low but uniform temperature.
;

174

ICE
brine system

CREAMS AND

ICES

The

direct expansion

may be installed in the cream storage, but would probably be found equally satisfacThe fruit storage, can storage, and other rooms of tory. that sort may be refrigerated by the brine system with excellent results.

The bricking and molding rooms
fairly

should be kept at a

low and uniform temperature. The brine system will be found a very satisfactory method of maintaining the proper conditions in these rooms. Brine hardening. Another and probably more important application of the brine system in the ice cream factory is There are two methods for hardening ice creams and ices. by which cold brine may be employed for hardening ice cream. One method is to set the cans of ice cream in a tank of cold brine and allow them to remain for 12 to 24 hours.
In this method a well insulated tank
is

partitioned off into

squares just large enough to hold a single can of ice cream.

Expansion
of cans.

coils

are located in the tank between the rows
is

The

brine

cooled by
to secure

ammonia

to a temperature

of about zero.
lating

An
The

agitator or a

pump

keeps the brine circuin all parts

around the cans

uniform freezing

of the tank.

large

cumbersome tank needed

in this

method of hardening may be dispensed with by using what
is

known as the drip method. The drip method. In this method
it is

of hardening, the brine

is

cooled in a brine cooler and piped from there to the hard-

ening room where

sprayed over the cans of
shelves,

ice

cream.

The cans are placed on draining

one above the other,

and so arranged that the brine will drain away as fast as This system of hardening reit is sprayed on the cans. quires less space than the brine tank method and in the opinion of many ice cream makerg is one of the most effi-

REFRIGERATION
cient

175
ice

and economical systems of hardening

creams.

For

various reasons, however, these systems of hardening are
gradually being replaced, particularly in the large plants, by
the direct expansion or dry air hardening systems.

The dry

air

hardening systems have several advantages
In the
first place,
is

over the brine tank or the drip systems.
the refrigerating effect of the expanding
in coils placed in the area to

ammonia
is

used be

be cooled, thus avoiding a loss
likely to

of efficiency due to the absorption of heat, as the case with a large body of brine. the system
is

Another advantage of
in the

that

it is

more economical
is

use of space.

Where

the dry air hardening system

used a large quantity

of ice cream can be stored in a rather small area. the fact that the storage rooms are kept perfectly dry,

Probis

ably one of the greatest advantages of the dry air system

mak-

ing

it

much

easier to keep the air pure
air air

and sweet.

There are two dry
is

known

as the

still

One system system and the other as the cold
hardening systems.
is

blast circulating air system.

The

still

air

system, as the name implies,

operated

without any circulation of air in the hardening rooms, other than that circulation due to a difference in temperature. It
is

claimed by some that
air

still

air

is

just as efficient as circu-

lating air

and does not require any kind of mechanism for
currents; nevertheless, the circulating
is

circulating the
air

system seems to be the most popular and
circulating air system
is

gaining in

favor.

The
tem
in

similar to the

still

air sys-

lation

most respects, but the air is kept in constant circuaround the cans by means of a large fan. In this
air is forced

system the cold

downward
in

in a strong draft

from the bunker rooms overhead,

which the expansion

176
coils

ICE

CREAMS AND

ICES

The advantage of this s)stem is that are located. more uniform hardening is obtained. There is little chance
for the dead air to stand in the spaces between the cans.

The consensus

of opinion
is

among

practical ice

cream men

is

that this system

more economical than the

still

air system.

CHAPTER XV
THE ECONOMICAL OPERATION OF THE REFRIGERATING PLANT
The economical
some knowledge
operation of a refrigerating plant requires

of the principles of refrigeration and the
It

properties of the refrigerating agent.

has been pointed
applied in the ice

out that mechanical refrigeration

may be

cream factory
dition,

to

harden

ice

cream, either by the brine or by
In adartificial

the dry air process, and to cool briiie for the freezers.

many

factories

now make

their

own

ice

by

refrigeration.
is

Considering the extent to which this system
in ice

employed

cream

factories, the subject of its eco-

nomical operation becomes worthy of serious consideration on the part of the ice cream manufacturer.

Ammonia.

The whole

discussion

of

the

economical

operation of a refrigerating plant centers upon the peculiar
properties of ammonia.

Under ordinary
of

conditions,

am-

monia

is

a gas.

It

may

be liquefied quite easily by com-

pressing and cooling.
erating agent
fied atis

The value

ammonia

as a refrig-

due largely to the fact that it can be liquecomparatively low pressures and ordinary tempera-

tures.

The

refrigerating capacity of a plant depends upon the
length
varies

number of pounds of ammonia evaporated in a given of time. The weight of a cubic foot of ammonia gas

(See Table I.) The with the temperature and pressure. weight to a cubic foot increases with an increase in the
177

1

78

ICE

CREAMS AXD
This difference

ICES

pressure and temperature, and decreases as the pressure and

temperature decrease.

in the densit)- of the

gas under different conditions should be kept in mind in
operating a refrigerating plant, to avoid a loss in efficiency

due to carrying too low gauge pressure on the suction
or too high gauge pressure on the compression side.
grees and

side

For example, if the temperature of the gas is zero de1 6 pounds pressure on the suction side, and is compressed to 115 pounds at 70 degrees in the condenser, it
be necessary to have
sufficient

will

cylinder capacity to

handle 3.63 cubic feet of gas each minute to produce the eft'ect of one ton of refrigeration in 24 hours. (See Table II.) If the temperature and pressure are reduced to 10

—

degrees and 9 pounds respectively, it will require the discharge of 4.73 cubic feet of gas each minute to produce
the effect of one ton of refrigeration in 24 hours.

A

loss in capacity will therefore be the result of a lower-

ing of the temperature and pressure of the gas on the low

Fig.

57.

The Jamison Revolving Door

for

hardening rooms.

pressure side.

A

to discharge 3.63

machine with sufficient cylinder capacity pounds of gas each minute will produce

ECONOMICAL OPERATION
the effect of one ton of refrigeration only
at zero degrees Fahrenheit

179
the gas
is

when

and 16 pounds pressure on the low side and 115 pounds pressure at 70 degrees on the high side. There would be a loss of about 20 per cent, in the refrigerating capacity of the machine if the pressure on the low side were reduced to 9 pounds, because at zero degrees and 16 pounds pressure a cubic foot of the saturated gas weighs .1108 pounds, while at10 degrees and 9 pounds

on the low side should be such that the boiling point of the ammonia will be 7 to 10 degrees below the temperature to be maintained in the brine tank, cooling rooms, and other The lower the pressure on the places to be refrigerated.
suction side, the lower will be the boiling point of the

am-

monia, and the
of

less will

be the weight of each cubic foot

ammonia

gas.

Since the refrigerating capacity of a plant

depends upon the number of pounds of ammonia handled in a given length of time, this data is of considerable importance to the operator of a refrigerating plant.

The
is

ried as low as conditions will permit.

pressure on the high side, however, should be carThe reason for this
will require less

that

it

power

to drive the

compressor

if

the gas can be condensed at a low pressure.
the cooling water used in the condenser.
case, the cost

The pressure
This being the
into conit

required will depend upon the amount and temperature of
of water and power must be taken
the cost of water
is

sideration.

Where

very great

may

be more economical to condense the ammonia at a higher pressure and use less water, even though it requires more

power

to operate a compressor in that way.

To

ascertain

iS:

](-\<.

rui'

\MS \\n UM"s

ECONOMICAL OPERATION

183

the conditions under which the plant can be operated most
economically, the cost of power must be checked against
the cost of water.

The type

of condenser used

may have some

effect

upon

the pressure which must be carried on the high or compression side of the system.

The atmospheric condensers usually show a higher pressure than do the submerged condensers, even with the same initial and final temperatures, but the quantity of water used is small compared with that used
in the other type of condenser.
is

atmospheric condenser

that

Another advantage of the where there is a tendency for
the coils can be cleaned

the water to deposit mineral

salts,

more

easily because they are exposed.

The disadvantage

of

this type of condenser, aside

from the higher pressure which, as a rule, must be carried, is that they are not uniform in action, but depend to a greater or less extent upon weather That is, they work best when the air is dry, beconditions. cause of the rapid evaporation of water from the surface of
the
coils.

Of
is

course, this evaporation will not take place

when

the air

saturated with water vapor.

The double
condenser in
atmospheric
action.

pipe condenser has displaced the atmospheric

many

places

because

it

is

independent of

conditions

and therefore more

uniform

in

The most

striking advantage of the double pipe

system, however, is that the ammonia gas is brought into very intimate contact with the cold surface of the condensing coils. The result is that this type of condenser is very
efficient in its operation,

provided the cooling water

is

not too

warm when

it

reaches the condenser.

The

flow of water

through the coils may also be adjusted to any condition of temperature and pressure. The proper use and regulation of power and cooling water

i84
will
is

ICE

CREAMS AND

ICES

do much to reduce operating costs, but unless provision made to prevent the absorption of heat at other points than those areas which it is intended to cool, the gains made in the engine room may be lost in the cooling rooms because
of poor or insufficient insulation.

The
The
will

insulation

is

one of the most costly and important

items in the construction of cooling and hardening rooms.
greater the difference between the temperature inside
the cooling

room and

the external temperature, the greater
sort.

be the need of sufficient insulation of the best

To be
first-class

a good insulator a material must, of course, be a

non-conductor of heat.

It

should also be

fire

and

moisture-proof and non-odorous.

The

insulating materials

commonly employed are minand certain
special

eral wool, hair-felt, mill sha\ings, cork

cork preparations.
quite extensively

Dead

air
still

spaces were originally used

and are

used to a certain extent in
insulating.
It is so

refrigerator construction as a
difficult,

means of

however, to build
of air

certain

amount

such a way as to prevent a circulation in what should be the dead
in

air spaces, that the
tion.

tendency

now

is

towards solid construc-

A

wall so built simply consists of layers of various
pitch, asphaltum, or

materials, using mineral wool, saw-dust, or cork for insulating,

and

water-proof paint to pro-

tect the insulation

from moisture.

The proper

protection

from moisture is very important. Many substances are good insulators when dry but take up moisture readily and become wasteful because of the fact that they are not good

when in a moist condition. one of the best materials to use because it comes very near having all of the qualities of a good insulator. It
insulators

Cork

is

is

a first-class non-conductor,

is

not affected by moisture,

ECOXOMICAL OPERATION
and although
substance.
it

185

is

not fire-proof,

it

is

a very slow burning

The
tention.

insulation of hardening

rooms

requires special at-

In the dry air hardening rooms a temperature of
is

about zero

maintained constantly.

It

requires the best

of insulation, properly protected from moisture, to maintain

such a low temperature economically.

Eight to ten inches

Fig.

S9-

Interior of a

Dry Air Hardening Room.

of ground cork, cork board, or some similar insulator furnish the necessary insulation for the dry air hardening rooms. In some cases one or more dead air spaces are

provided

Water-proof paint, special kinds of paper, prepared roofing, and pitch are the substances frequently used to protect the insulation from dampness.
also.

i86

ICE

CREAMS AND

ICES

Slush boxes and brine tanks should be insulated with
equal care and special precautions must be taken to protect
the insulation

from dampness.

In

all

cases insulation will

be found quite expensive, but economy of operation should not be sacrificed in order to reduce the cost of construction.

What has already been said regarding the operation of a compressor for cooling rooms and other ice cream refrigeration, applies also to the

manufacture of

ice.

Since

many

Fig. 60.

Freezing Tank, Can

Filler,

Hoist, and

Dump

in

an

ice

cream factory.
factories, both large

and small, aim

to

make

all

or a large

part of the ice which they use, the subject of ice
is

making

one of no

The
half

importance to ice cream manufacturers. ice making capacity of a compressor is rated at onelittle

its refrigerating capacity. Theoretically, a one ton machine should make one ton of ice in 24 hours after the water has been cooled to 32" P., but in actual practice the ice making capacity of a machine is about half its re-

ECONOMICAL OPERATION
frigerating capacity, because of the

187
losses

many unavoidable
loss of ice in

due to exposure of the freezing tank, off and in handling.
Ice cans.

thawing

The

ice

is

frozen in metal cans which are

placed in a tank of strong brine.

expansion

The
The
tures

The brine is kept cold by connected with the ammonia compressor. time required for freezing ice will depend upon
coils

the size of the ice cans and the temperature of the brine.

following table shows the approximate time required

for freezing various sizes of ice cakes at different tempera:

Table

III

Size of Ice Cans

i88

ICE

CREAMS AND ICES
The
freezing point of brine at different
is

to be maintained.

degrees of concentration

shown

in the following table

:'^

Table IV
Pounds of
salt to

each gallon of water

.

ECONOMICAL OPERATION
agitator to keep the brine in constant circulation.
tion to tliese there must, of course, be a certain

189
In addi-

amount of

other apparatus, such as an ice hoist, thawing apparatus,

can

fiher, etc.

The
coils of

brine tank

is

provided with necessary expansion
It will

require approximately 100 to 125 square feet of pipe surface to each ton of ice capacity.

ample area.

The

agitator.

The

brine in the tank must be kept in

In small tanks a propeller-like agitator of 12 or 18 inches diameter

constant circulation by an agitator of some sort.

running at about 200 revolutions a minute, or a small centrifugal

pump,

will insure a sufficient circulation of the cold

brine around the freezing cans.

The freezing cans are made a little smaller at the bottom than at the top and hold from 50 to 400 pounds of ice, the size and dimensions of the can being varied to suit conditions. The cans are usually made of about No. 16 gauge material. The following table - shows the dimensions of different sizes of ice cans and the weight of the cakes of ice from each
T.\ELE

V

Weight of
ice in

cake

190

ICE

CREAMS AND ICES

Note: The brief discussion given in this chapter is intended to give the beginner a general idea of the subject Those who desire more detailed information on mechanical refrigeration should conof Mechanical Re& Collins Co., Chicago, and " Modern Refrigeration Machinery," published by Wiley & Sons, are suggested as suitable references for students. Steven's " Mechanical Catechism," published by Laird & Lee, Chicago, and Levey's " Refrigeration Memoranda," published by Nickerson & Collins Co., Chicago, are suggested as helpful references for those who are particularly interested in engine room practice.
sult

some standard work.

Siebel's

"

Compend

frigeration and Engineering," published by Nickerson

CHAPTER XVI
SCORING ICE CREAMS AND ICES

The problem of scoring ice creams and ices is a new one and presents some difficulties which are not encountered in
scoring other dairy products.
flavor for ice

In the

first place,

the ideal

more variable than the ideal flavor of other dairy products and depends upon the kind and amount of flavoring used and the presence or absence of other substances which blend with and modify the added flavoring material. Such a blend or combination, even if it
cream
is

far

be unintentional,

is

not always displeasing.

Our

ideal or

our standard for comparison will have to be varied somewhat to make it apply in individual cases. For example, if

we

are scoring vanilla ice cream,

its

flavor

must be judged

according to the quality of the vanilla flavor which has been

imparted to the

ice

cream.
is

The
subject

flavor of ice cream
it

so variable that
in

it

will

be neces-

sary to discuss

under several heads
angle.

order to view the

from every

We shall first consider the flavors

imparted by the extracts or other added flavoring material. The qualities of flavor imparted by the flavoring material may be designated as high, loiv, mild, harsh or sharp, and
foreign.

The

flavoring material itself

may

be of excellent

amounts or in too large amounts, the results will be far from satisfactory. High flavor is characterized by the presence of large
quality, but if used in insufficient
igr

192

ICE

CREAMS AND

ICES

amounts of the flavoring material.
to the ice cream.

In some cases an excess

of flavoring material will impart a sharp or a bitter flavor

A

poor quality of flavoring
is

may have
if

the

same
sible,

effect

;

hence,

it is

quite important to determine,

pos-

whether the bitter flavor amounts of flavoring material.
reduction in score should be

of course, just as undesirable as

due to poor quality or large Poor quality of flavoring is, an excess of flavoring, and a
accordingly.

made

on the other hand, may be due to insuffiflavoring material and also to the flavor's being cient or weak Certain some other obscured by substance or flavoring. flavors must not be heated, because of their volatile nature. Such flavoring substances, if cooked, give the ice cream a very low flavor which is difficult to classify. Low flavor, however, must not be confounded with mild flavor. Mild flavors are as a rule the most pleasing and desirable. Natural flavors, such as the fruit and nut flavors, are mild and not very pronounced. If the flavor can be recognized, the ice cream should not be scored off on account of low
flavor,
flavor.

Low

Harsh or sharp

flavors are usually due to the use of in-

ferior flavoring substances, but

may

from the use of too much flavoring
tration of this defect
is

the flavor

some cases result A good illusobtained when quite large
in

extract.

lemon or orange extract are used, giving a lemon or orange flavor which is due to the lemon oil enInferior and artificial extracts lack the fine, mild tirely. qualities of the high grade extracts and frequently give a
quantities of

very pronounced, but not pleasing, flavor to the

ice

cream.

Foreign flavors are to be considered as defects, but the extent to which ice cream should be scored off for foreign flavor will depend upon the source of that flavor. For ex-

sometimes added to other fruit to Should any of the oil from the rind of the lemon find access to the mixture it is likely to impart a lemon flavor where it is not wanted. The flavor of

lemon

in

such a case would be a foreign flavor but not of
sort.

a particularly undesirable
fruit,

Bad

flavors

due to bad

cream, poor gelatin, fermented syrups, overripe or unsound

and rancid

nuts. are foreign flavors for

which a larger

reduction should be
the ice cream

made

in scoring ice cream.

Fruit and fruit juices
if

may
is

impart undesirable flavors to

unsound or the juice fermented. The naturally mild flavor imparted by sound fruit may be distinguished quite easily from the artificial flavors. An
the fruit
artificial flavor is

not entitled to as high score as a natural

flavor.

Nut
flavors.

flavors are to be judged in the same

way

as fruit

which the nuts have been prepared should also receive attention. It should be noted whether or not the nuts have been blanched, finely chopped, and evenly distributed through the ice cream. Syrups and sugar may be used in excess, making the mixture too sweet, or an insufficient amount may be used, in which case the ice cream would have a flat flavor. Sometimes a sour or yeasty flavor may be imparted by the use of a syrup which has begun to ferment. The flavors imparted by the cream are the most important from a hygienic standpoint. The flavor given to ice cream by good, pure cream, milk, and condensed milk is Defects in the flavor of ice cream due to rich and creamy. the use of tainted cream or milk are as a rule easily deThese flavors are usually described as " bitter," tected. " cowey " or " barn odors," " weedy," " sour," " musty,"
in

The way

194

ICE
" cheesey."

CREAMS AND
in

ICES
such

and
here.

These terms are

common
little

use in

scoring other dairy products as to need but
sibly the bitter flavor

description

All of these flavors are easily recognized, except pos-

which may come
It

also

from flavoring

material, nuts, or fruit.

has been pointed out elsewhere,

that off flavors in milk

a high bacterial content.

and cream are usually associated with For this reason a large reduction

should be

made

for these unclean flavors.

is the body and texture There is some difference of opinion as to whether the body and texture should be judged together The claim is or be considered as two separate characters. made that the conditions which produce good body must necessarily produce a good texture. Body and texture, whether considered together or separately, are of no little importance, but they are characters which are difficult to describe. In very general terms, body may be said to be that quality which gives weight and subAlstance to the product and enables it to stand up well. most any one will recognize the difference in the holding qualities of different batches of ice cream at the same temThe ideal body is that which is produced by milk perature. Ice cream containing the proper proportion of milk solids. solids has a certain permanence or holding quality and is firm but not sticky or pasty at low temperatures. The absence of that sticky or pasty condition is due partly to the presence of the milk solids and partly to proper swell. Ice cream which is over frozen, if it does not churn, has a heavy, pasty consistency. Such ice cream may have the permanence and holding qualities without the lightness which is characteristic of good ice cream. It is for this reason that some prefer to consider body and texture separately.

Next

in

importance to the flavor

of the ice cream.

SCORING ICE CREAMS AND ICES
product.
light.

195

Texture refers to the grain or to the finer quahties of the A well frozen ice cream will be very smooth and
This
is

the proper texture for ice cream.
ice

The

conditions affecting the body and texture of

cream are the amounts of milk solids present, the presence or absence of a stabilizer, and the way in which the cream
is

frozen.

The term milk
milk

solids does not

mean

fat alone but all

solids, including casein,

milk sugar, and albumen.

The

milk solids other than fat give the ice cream a good body,
a pleasing flavor, and a high food value.
frozen, ice
solids will

When

properly

cream containing a sufficient amount of milk also have a very smooth texture.

Stabilizers are used chiefly to prevent the formation of

texture.

cream a coarse or granular and frappes, a granular texture If there is an excess of stabilizer presis very undesirable. ent or if the ice cream has been frozen too long in the freezer, it will have a close, sticky texture, for which a reduction in score should be made. The manner of freezing will affect the swell and thereice crystals that give the ice

Except

in granites

fore the texture of the ice cream.

Distinction should be

made, wherever

between a granular texture due to the absence of a stabilizer and a granular texture due to insufficient freezing or to refreezing soft or melted ice cream
possible,

without agitation.

The appearance
affected by the
to

of the finished product will also be

manner of freezing, but the term refers more Since ice creams the coloring and finish of the product.
ices are

and
its

essential.

The appearance

used as a dessert, a tempting appearance is very is therefore more important than

place on the score card

would

indicate.

The

points to

196

ICE

CREAMS AND

ICES

take into consideration under this heading are indications

good or poor workmanship, appropriate colors, uniand in the molded ice creams, the uniformity of layers and the clearness of outline in the molded The last place on the score card is given to packobject. age, but to a certain extent appearance and package must
of

formity in colors

;

be considered together.
refers to the way in which the ice cream packed for market. The cans should be well filled and should have a piece of parchment paper under the cover. Any indications of brine or salt under the cover, dirty parchment paper, or other indications of careless packing will
is

The package

detract

from the

score.

Score Cards for Ice Cream

Mortensen's score card as given

in Bulletin 123 of the

Iowa

station
"

is

given below.

Flavor Texture
Richness

45 25
15

Appearance
Color
Total
"
I.

10
5

100

Flavor.
" Definition of

Good

Ice

Cream Flavor

"

The cream

flavor

must be clean and creamy, and com-

bined with flavoring material which blends with the cream
to a full and delicious flavor.

:

:

SCORING ICE CREAMS AND ICES
" Defects in Flavor

197

" I. Defects due to the use of flavors which will not blend with the other ingredients. " 2. Defects due to cream used

most noticeable toward the bottom be due to improper packing or by cream which was manufactured withis

" Coarse.
" Sticky.

This defect

may be due
soft.

to the use of too thin

cream, or to packing while too

This is due to fillers such as gelatin, sweetened condensed milk, glucose, etc. " Buttery. This defect is due to the use of cream which has been partially churned before freezing, or to cream which
enters the freezer at too high a temperature.
It

may

also

be due to operating the freezer at too high speed or to some
defect in the construction of the freezer. " Too Soft. Due to improper packing after freezing.
"

When

judging cream containing nuts,

fruits, etc.,

due

allowance should be given for the presence of such ingredients.

" III.
" Ice

Richness.

cream containing the amount of butter fat required by the State pure food law should be considered perfect in
richness. " The richness
is

determined by making chemical analysis

for fat.
" IV.

Appearance.

" Ice cream scoring perfect in appearance should be clean and neatly put up, and in a clean container. " Defects:

Cream
over
ice

of unclean appearance; lack,of parch-

ment

circle

cream

;

dirty

container

;

rusty con-

;

SCORING ICE CREAMS ANID ICES
tainer
"
;

199

dirty

ice

cream tub
ice

;

old

tag strings

attached to

handle of tub.

When

judging brick

creamg special attention should

be given to the uniformity of the layers, to the neat folding of the parchment wrapper, and to cleanliness and general

appearance of the package.
"

V.

Color.

" Ice

natural color imparted to
If

cream of perfect color is such as contains only the it by the flavoring material used. color is added it should harmonize with the particular

flavoring used.
" Defects in Color
:

Too high

color

;

unnatural color such
flavoring

as colors different

from the color of the natural
if

material used.
" Individual molds,
sible the

colored, should be as nearly as pos-

same color

as the object they represent."

Washburn's score card as given Vermont station is as follows
"

in Bulletin 155 of the

Flavor

45

Body
Texture

20 20
10
5

Permanency Package
Total

100

"Flavor:
to taste with

To be that of clean, sweet cream sweetened cane sugar; the score to be cut for any flavor

of spur cream, and cut severely for any dirty flavor, and

200
but
little if
is

ICE

CREAMS AND

ICES
if

too sweet or not sweet enough, or

the added

flavor

too high or low, for these are largely regulated by

trade demands.

"Body:
It

To be

firm,

mellow and

slightly elastic

under
less.

pressure of the finger at a temperature of i8° F. or

must not be rubbery or too weak.
" Te.rture:

To
;

be smooth, creamy, and free from coarse
if

water crystals

the score to be cut moderately

too coarse,

and severely if inclined to be sticky or doughy. "Permanency: To have a reasonable standing-up power on an ordinary cool dish, and to offer some resistance in the mouth instead of melting and disappearing as liquid almost immediately upon being tasted. "Package: To be clean, tidy, and free from evidence of slovenly workmanship."
which
In both of these score cards 45 points are given to flavor, is about a correct estimate of the importance of good

flavor.

Upon

the

other points
'

there

seems

to

be some

seems to the authors that a compromise could be made between these two score cards which
difference of opinion.
It

would give a more
In the
is

satisfactory score card.

in judging the quality of ice cream need of considering " richness " by itself nor does it follow that the ice cream which contains the amount of fat required by law is ideal. Upon this point there is a
first

place,

there

little

wide difference of opinion among authorities. The preference of the consumer is not unanimously in favor of rich ice cream nor are the pure food laws of the various States uniform in regard to the per cent, of butter fat which ice cream must contain. Pernjanency is a quality which may well be considered

:

SCORING ICE CREAMS AND ICES
under body.
ance."

201

Color could be considered under " appearthese alterations and substitutions the

By making

score card would be as follows

The University
Flavor

of Nebraska's Score

Card
45
,

Body
Texture Appearance Package
Perfect Score

20

20
10
5

100

CHAPTER XVII
THE
ICE

CREAM FACTORY;

ITS

LOCATION AND EQUIPMENT
is

A good

location for the factory

one of the

first

problems

that confronts the person

who

contemplates entering the

ice cream business in any locality. It is a problem which must be solved for each case separately, because no general

rules will apply in all cases.

The

location of the factory will

depend upon various

local conditions

such as the size of the
facilities,

town, class of trade to be served, location of the customers,
prospects of future growth, transportation
cost of

and the

property.

A

careful

consideration of these and

various other local problems will aid greatly in selecting an

advantageous location.
of a suitable building, or
ing, the

The next problem is the what is more difficult and

erection

perplex-

remodeling of an old one to meet the needs of the proposed business.

The

interior

fully planned.

arrangement of the factory should be careIn a building which is specially constructed
is

for factory purposes, the matter of interior arrangement

much simpler. It is who are just starting
poses.

often necessary, however, for those
in the ice

cream business

to

make use

of a building which was not constructed for factory pur-

Under such circumstances

the adaptability of the
its

building to ice cream factory purposes as well as

advan-

tageous location must be taken into consideration.

One can

find buildings of every sort

and description used

THE

ICE CRI'.AM FACT( )RY
Pnvafe
Uriveivav

203

Pnrtifeffni^ey/ay

Fig. 61.

First-floor

Plan of a well-arranged factory.

^J/iifA
Fig.
62.

Second-floor

Plan of the same

factory.

204

ICE

CREAMS AND

ICES

Uijt/i»)j fui<f(fiy^

a

J

-I

I-

o

Ph

fx.

bo

.o.sr

THE
to the

ICE

CREAM FACTORY

205

for ice cream factories,

some of which are well adapted purpose for which they are used, while others are

decidedly inconvenient and must result in a lowering of factory efficiency. To avoid such inefficiency wherever possible,

the general dimensions of the building,

amount

of

light, facilities for ventilation,

and the character of the

walls,

floors,

and the

ceilings should be taken into consideration.

The dimensions

of the building should be sufficiently

Fig. 64.
out.

Freezing Room in an ice cream factory. Note the abundance of light, good ventilation, and sanitary construction through-

large to

accommodate

all

the necessary machinery with

some

allowance for the future growth and development of the
business.

As

a rule
is

it

seems that a more economical use
is

of floor space

obtained where there

not too great dif-

ference between the length and breadth of the building.
Sanitation, however,
in the
is one of the primary considerations arrangement of the factory. This necessary sanita-

tion

may

be secured without making the factory a " show

2o6
plant."

ICE
The

CREAMS AND

ICES

sanitary measures to be observed are such

as are required

anywhere

to facilitate the task of keeping

the factory in a cleanly condition, to prevent contamination of the ice cream, and to protect the health of the employees.

Light and ventilation are of greater importance than some factorymen suppose. Light, and particularly sunlight, is detrimental to germ life, while darkness and dampness are favorable to the growth of bacteria and molds. A proper s\stem of ventilation and plenty of light will do much' towards keeping the factory dry and free from musty odors. Aside from the greater danger of contaminating the ice cream in a dark, damp factory, these conditions are detrimental to the health of the employees.
a

A

dry factory

is

more healthful and agreeable place in which to work. addition to light and ventilation, the construction of
floor
is

In
the

quite important.

Floors of cement are the easiest to keep clean and will The floor should have a uniform slope toward a gutter or sewer trap so that water will drain off readily. Some prefer having the floors slope uniformly
not absorb odors.

towards a sewer trap in the center of the room, others prefer to have the floors slope towards a gutter running lengthwise of the room. Another plan which is sometimes
followed
is

to

have the
to
all

floor highest in the center

with a

uniform slope
such a plan
the
is

sides.

that the

The advantage claimed for center of the floor where much of

done is kept dry. Other material than concrete may be used for floors, but the aim should be to have the floors smoothly finished and as free from cracks
is

work

as possible.

The

walls and ceilings should also be smooth and of

sorne water-proof material so that they

may be washed

dowri

THE

ICE

CREAM FACTORY

207

without injury or deterioration. Cracks and ledges on which dirt can accumulate should be reduced to a minimum. Walls plastered with a special cement plaster will come very near meeting all of these requirements, and if given a smooth, white finish, look neat and are durable. Enameled brick and vitrified glass may be used in place of the cement plaster. Walls constructed of these materials are very neat in appearance and easy to keep clean.

The facilities for cleaning up the factory after the day's run should be convenient, otherwise the work is likely to be neglected. Steam and water connections can be so arranged that all machines as well as every part of the floor can be
easily cleaned.

Simplicity in the arrangement of

storage rooms

and

machinery

is

highly desirable.

Narrow passages and dark

corners increase the difficulty in keeping the factory sweet

and clean. Convenient placing of machinery must be considered with a view to reducing the amount of labor. Improved machinery has done much to reduce labor costs, to increase the efficiency of help, to affect a saving in time and material. The advantages accruing from the use of modern machinery may be lost or greatly impaired by an inconvenient arrangement of the machinery and storage rooms. Such practices as carrying cans from one end of the factory where they are stored, to the freezer which may happen to be at the
other end of the factory, or locating the freezers at a needless
distance from the hardening rooms, entail an unnecessary

waste of time and energy which can be saved by a little forethought. On the other hand, the machinery must not
be crowded together so closely as
to

make

the

to hamper the workmen or work of cleaning up more difficult.

2o8

ICE

CREAMS AND

ICES
fruit,

The
terials

storage rooms for sweet cream,

and other ma-

used

in the

mix should be

so arranged that the batch

mixers can be located near the place where these substances Such an arrangement greatly reduces the labor are stored.
involved in getting the various ingredients into the mixers.

The aim should be
to the place

to

have every
article is to

article

kept convenient

where that
is

be used.

The importance
hardening rooms
but
is

of the proper location of storage and

patent to any practical ice cream maker,
to the location of the

when

it

comes

wash room

there

evidence of a tendency to overlook the importance of a

well equipped and properly located

wash room.

Of

course,

circumstances differ in the different factories a!nd must
therefore govern the choice of location under various conditions.

of thorough cleansing and sterilizing must not be ignored. The practice of placing the washing and sterilizing apparatus in any odd comer in of utensils

The importance

order to economize in the use of floor space

is

not desirable.

More
place

or less water

is

sure to be spilled over the floor around

the vats in which the cans are washed.

To, keep such a

from becoming foul there should be an abundance of light and good ventilatjon. A visit to a number of different factories will reveal the fact that there is no uniformity of practice in regard to the proper location for the wash room. In many factories it will be found on the main floor or even on an upper floor in a well lighted, drained, and ventilated room. In other factories it will be found in a dark corner of the basement with but little light and ventilation. While the ideal location for -the wash room
is

not necessarily the second floor of the factory,

still it is

easy to see that utensils washed in a dark, sloppy room

THE

ICE

CREAM FACTORY

209

B

o o
bo

a

-a

3
U)

U

210

ICE

CREAMS AND

ICES

are not likely to receive as thorough cleansing as would be
the case
if

the

wash room were located

in a

more

cleanly and

healthful location.

The object to be kept in mind throughout should be to so arrange one part or department in relation to all others that the product will be passed through the various departments
by the shortest possible route. In other words, the process from the receipt of the raw material to the delivery of the finished product should be carried out without crossing operations. To this end certain operations are best carried For example, the weigh out in a certain part of the factory. can, sample jars, sample dippers, and other apparatus needed in sampling and grading milk and cream are usually found convenient to the place where the milk and cream are
taken into the factory.

The weigh can
where the
ing

or the scales upon which milk and cream

are weighed are usually on the receiving platform, but
scales cannot be so located without causing con-

some other operation, the weighIn some factories the milk and cream are put on an elevator and taken to the upper floor at once where they can be weighed, sampled, and graded without interfering with any other operations. Unfusion or interference with

may

be done elsewhere.

der such circumstances, the pasteurizers, coolers, homogenizers,

cream storage, and other equipment for the care and
also.

handling of the cream will be found on the second floor

In some factories the testing apparatus will be found

near the place where the receiving, sampling, and grading Such an arrangement does away wdth the necesare done.
sity of

carrying samples and sample jars from one part of

the factory to another.

THE
locations,

ICE

CREAM FACTORY

211

For some pieces of machinery there may be several any one of which may be selected. For example, the use of conveyors, cream pumps, and similar apparatus gives one some latitude in placing such machines as pasteurizers and homogenizers.

:a

J>.

1

r"')r-'f^°f~'"'

Fig. 66.

A

Duke-Doyle Can and Top Truck. for ice cream factories.

A

labor-saving device

The

pasteurizer and cooler

may be

located convenient

to the receiving platform so that the milk or

received

is

dumped

in a large receiving vat

cream as it from which

is
it

flows to the pasteurizer.

From

the pasteurizer the milk or

in the

cream runs over a cooler and from thence into holding vats cream storage rooms. Where these different machines can be so located that the cream flows from one to the other by gravity, there is but little piping to keep clean.

212

ICE

CREAMS AND

ICES

u

P-,

>

bo

THE
This
is

ICE

CREAM FACTORY

213

many

factories,

an advantage which should not be overlooked. In however, the pasteurizer and cooler must

be used for other purposes than pasteurizing cream for

Fig. 68.

The

Burrell

Sanitary Mill< Pump.

Fig. 69.

The

Burrell Sanitary Milk

Pump

taken apart for cleaning.

ice

cream.

In such factories the location of the pasteurizer
will

and cooler

line of business

depend upon the importance of the other which requires the use of these machines.

214

ICE
it

CREAMS AND

ICES

above, the cans

becomes necessary to elevate cream to a floor may be placed on a conveyor or on an elevator and taken up in that way, or the milk or cream may be emptied into a vat on the main floor and then elevated by means of a pump. There are advantages in both methods. In the first method the pump and piping are dispensed with, but it often requires more lifting and transferring of the cans of cream. If it is necessary to have the wash room on the second floor, also, there is an added advantage to this method since the cans must be brought up any way. The use of a pump and piping makes it possible to do the receiving, sampling, and grading of cream on the main floor with but little handling of the heavy cans of cream. It is also a more rapid method of handling milk and cream. The results obtained by this method are very satisfactory so long as the pump and piping are kept clean by regular washing and sterilizing. The only kind of piping to use
for such purposes
is

Where

the seamless, sanitary piping.
it

This

piping should be in such lengths that

will

be easy to handle

and

to

keep clean.

are best located near the rooms in which the sweet cream is stored. They are frequently located on the floor above the freezers. This is a very

The batch mixers

con\enient arrangement, since
the freezer by gravity.

it

permits the

mix

to flow to

Pumps

or compressed air

may

be

used to transfer the mix from the mixers to the freezers. Some such method must be adopted where the mixers and
freezers are on the

the cooked mixtures

same level. The kettles for preparing and for melting gelatin should be

somewhere near the batch mixers.

The

freezers are best arranged in batteries convenient

to the hardening

rooms so that the work of transferring

THE

ICE

CREAM FACTORY

215

2i6

ICE

CREAMS AND ICES
to

from the freezers
rapidly.

the hardening rooms

can be done

The hardening rooms may
bule, in order that the ice

be built with a double vesti-

cream from the freezers can be introduced at one end and the hardened ice cream removed for shipment from the opposite end. Where the hardening rooms are arranged in this way the shipping department is best located at or near the hardening rooms opposite the
freezers.

The shipping department
that
it

should be located in such a

way
In

will

be convenient to load the delivery wagons.

connection with this department there must be ample space

and storage space empty tubs. Beyond these general considerations, the interior arrangement of the factory must be planned according to the local conditions. Impropei' and inconvenient arrangement of machinery and equipment increase operating expenses.
for the storage of ice, and an ice crusher, for

In

many

instances

a

slight

rearrangement

will

make

it

same amount of work with less help. Another very important point to keep in mind in planning an ice cream factory is the prospect of future growth. It is not a wise polic}- to build and equip an up-to-date factory without making some provision for an increase in the volume
possible to do the

of business at a future date.

The kind and amount of machinery needed for an ice cream factory will depend upon the size of the factory and its location. In ice cream making as in all other manufacturing, improvement in machinery and methods has gone hand in hand with the development and expansion of the industry. Except in the very small plants, the machinery installed should be of the most modern type. Such ma-

THE

ICE

CREAM FACTORY

217

:

2i8
chinery
is

ICE

CREAMS AND ICES
machinery of modern

expensive, of course, but a properly constructed

factory, equipped with the necessary

type, properly placed, will account for fylly 50 per cent,

of the factory efficiency.

ice

For a factory capable of producing about 500 gallons of cream a day, the machinery needed would be about as
I

modern ice cream will have to be modified somewhat in order needs of different localities. In some cases

such things as the separator, pasteurizer, and cooler will not be required.

Some may

not like the continuous freezer,
that the small
installation of

and others, in very small factories, may feel volume of business done will not warrant the
anything but a tub freezer.

All things, including present

must be taken into consideracream factory. The ice cream freezer, which is one of the most important pieces of equipment, is now manufactured in several types. The oldest and most familiar type is the upright freezer. These freezers are well adapted to the needs of tub small ice cream factories or to the manufacture of ice cream in connection with some other line of dairy manufacturing. For a plant making over 150 gallons a day it will found more economical as a rule to use one of the more be modern freezers.
prospects,
tion in selecting the equipment for an ice

demands and future

Brine freezers are so called because cold brine instead of an ice and salt mixture is the refrigerating agent used.

220

ICE

CREAMS AND

ICES

These freezers are of several types, some of which are continuous in their operation, and others are known as
intermittent or batch freezers.

The continuous
frozen mixture
is

freezer

is

so constructed that the un-

introduced at the same time that the

One
frozen ice cream
is

of the larger

Tub

Freezers.

being discharged.

One
is

of the most
is

common

types of continuous ice cream freezer

the disc

type in which the necessary agitation
of rapidly rotating discs.
cold brine
is

given by a series

These

discs are hollow

and the
series of

kept circulating through them.
it

A

scrapers remove the ice cream as fast as

freezes on the

THE
discs.

ICE

CREAM FACTORY

221
is

Above

the discs and at one end of the freezer

a
is

worm which works
is

out the frozen ice creE^m.

The mix

introduced at the opposite end of the freezing chamber and
frozen as
it

passes through the machine. freezers using cold brine as a refrigerating
in several sizes

The batch

agent are made

and with considerable modi-

Fig, 73.

The Disc Continuous

Freezer.

fication

of structure.

These machines are made

in

both

the horizontal and vertical type.

are used very extensively. surface for their capacity, a fact which makes
operate them satisfactorily with

The horizontal machines They have a large freezing
it

possible to

brine at a slightly higher

temperature.

222

ICE CREAAIS
ice

AND

ICES

In selecting an
that they
all

work

for

cream freezer it should be remembered and aim to accomplish the same thing.

The

points to be considered particularly are durability, ca-

pacity,

and

efficiency.

The

Ft.

Atkinson Freezer.

Durability and capacity.
be

An

ice

made of good

material, otherwise the joints will

cream freezer must become

leaky, the parts

exposed to the action of the brine will
life of
is

become corroded, and the
Simplicity in construction
the machine

the machine will be short.

highly desirable in order that

may

be easily cleaned.

A

machine

in

which

THE
every part
is

ICE

CREAM FACTORY
is

223

accessible for cleaning or that can be taken

apart and assembled quickly

sure to be taken care of

better than one which does not possess this advantage in construction.

The

walls

of

the

freezing

heavy enough

to stand the pressure of the brine

chamber must be which is

circulated in the brine chamber.

In the tub freezers, the

Fig.

75.

A

horizontal

Batch Mixer.

denting

can must be heavy enough so that there is no danger of it when the ice and salt is packed around it.

The freezer selected must be of ample capacity so that an unexpected demand for ice cream can be taken care of without crowding the capacity of the machine too much. The efficiency of a freezer will depend upon its conThe surstruction and the material of which it is made.

224

ICE

CREAMS AND

ICES

faces through which heat must be conducted are usually
of copper because that metal is a good conductor. Other surfaces through which heat is not to be conducted should be protected by insulation. The best type of a tub freezer is one having a heavy copper can and a substantial cedar tub. The tub must be strong enough to stand the hard usage to which it is subjected and thick enough to serve as an insulation to reduce the absorption of heat from the outside. In selecting a brine freezer the number of wearing parts, the number and strength of gears, and the construction of the stuffing boxes are

made

points that should also be

taken into consideration.

Few wearing
simple

parts

and

power

transmis-

sion are always desirable.

Brine freezers are more
complicated and
parts

many
old

of

them have more wearing
than
the

tub
the

freezers.

One

of

greatest sources of trouble
is

with these machines
the
stuffing

boxes.

boxes should ^e so designed that the Fig. 76. A Progress Batch Mixer, packing can be kept well set up to prevent the brine from leaking through and corroding the bearings. Provision must be made for keeping
stuffing
all

The

bearings thoroughly lubricated.

The

best results

are obtained from any

freezer

only

THE
when
point before
it

ICE

CREAM FACTORY
mix
is

225

the temperature of the
is

reduced to the proper

put into the freezer.

A

perfect control

of temperature, and thorough mixing are obtained by using

a properly constructed batch mixer.

A
in

some

batch mixer of must be used any place where ice
sort

is made. The which a batch mixer should accomplish are a uniform cooling of the mix and a uniform mixture of

cream

things

the various ingredients.

These

machines

are

made

in various types

and with a capacity of 100 gallons and over.

Some

of these machines

resemble the ordinary

cream ripener
the
agitation

in
is

which
pro-

duced by a rotating holFig. 17A small size Progress Mixing low coil through which Vat. the cooling water flows. Another type is the upright mixer in which the cooling water is circulated in a water jacket around the vat which holds the mix. The agitation is produced by a two blade This agitator agitator located at the bottom of the vat. prevents the sugar from settling to the bottom. The entire machine is well insulated to insure a more economical
use of the cooling water.

226

ICE CRKAAIS

AND

ICES

factories, small For volume of busiwhere the warrant the ness will not

installation

of

a a

large

batch
starter

mixer,

small

can

may be used
These cans
a

instead with very satisfac-

tory results. are
fitted

with

water

jacket and agitator giving
a fairly

the temperature.

good control over These
be obtained in

cans
sizes

may

from ten gallons up

and are well adapted to
use in the small factories.
"«.

Perpendicular Mixer.

Batch

The
portant

ice

crusher
of
is

is

a very im-

part

tlie

equipment

whether the plant

equipped with

brine freezers or not.

The

vari-

ous makes of ice crushers are very
similar in design.

Practically

all

them are so made that the machine can be set to crush the ice
of
into

pieces
is

of

any desired

size.

Not only

the ice crusher a labor

saving device, but hy crushing the
ice into pieces of

uniform

size the
Fig. 79.

results

obtained both in freezing

A

small Victor

and packing are more uniform and
satisfactory.

Starter

Can which may-

be used as a Mixer.

THE

ICE

CREAM FACTORY

227

Can washers. Where any great vohime of business is done, the expense of washing cans is considerable and the results are
often unsatisfactory, as
is
it

sometimes

difficult

to

228

ICE

CREAMS AND ICES
Sterilizer

and

drier.

has who one watched the operation of can washing in any estab-

Any

lishment
fore

knows

that be-

many

cans have been

washed the water is very impure, and very frequently the help entrust-

ed with
properly
draining

this

work do not
and

realize the

importance of
rinsing

each
this

can.

To

overcome
Fig. 82.

difficulty,

The Ft. Atkinson Can Washer.
used.

Ice

Cream

an apparatus for rinsing,
drying

sterilizing,

and

may be

The

rinsing

may be

done by inverting the can over a water The sterilizing may be done either jet. by steam or scalding water. One type of sterilizer, which is practically automatic in its operation, uses hot water in which the wash water is rinsed off and the cans sterilized as they pass through the machine.

The

hot cans dry quickly, but in
is

many

factories the drying

hastened by
air
blast.

inverting
Sterilizing

each

can

over

an

germ

life

and drying not only destroy but prevent the cans from rust-

-^'S- 83-

The Prog-

mg

and thus prolong their period of use-

Sterilizer,

fulness.

THE

ICE

CREAM FACTORY

229

Fig. 84.

The

Ft.

Atkinson

Sterilizer.

Fig. 85.

The Jensen Can Drier and

Sterilizer.

230

ICE

CREAMS AND ICES
Another piece of apthe kettle for cooking
is

Kettle for Neapolitan ice cream.
paratus which
is

quite important

Neapolitan ice cream mixtures. These kettles may also be used for other purposes, such as preparing simple syrups and

Fig. 86.

The Progress

Ice

Cream Can Washer and

Sterilizer.

for melting gelatin.
is

small as compared with the

Although the demand for cooked cream demands for uncooked cream,

every well regulated factory should be provided with this
piece of equipment.

The

kettle

may be made

especially for

that purpose, but any kind of arrangement
is

heated over steam or hot water will

whereby the mix answer the purpose.

THE
For small
the steam
kettle.
is

ICE

CREAM FACTORY
a steam jacket.

231

factories a double boiler will do very well.

The

special kettles are
is

made with
type

In one type,
jet

generated by a furnace or a gas

under the

A more

common

is

the one in which the steam

supplied by the regular steam boiler.

The apparatus and equipment
But machines, such

thus far discussed

may

be

considered as essential to both large and small factories.
as the homogenizer, for instance, are

confined to fairly large establishments.

The homogenizer.
are of two types.

The modern homogenizing machines
is

In one type the machine

provided with

RELIEF VALVE

DISCHARGE VALVE

Vv^^vW^ftY^
I

A^.wi.w^v^^^_y

I

Fig.

87.

Longitudinal

section through the Gaulin Homogenizer, showing the agate valve. See also Fig. 25.

an accurately seated agate valve which is held in place by a strong spring. The pressure from a series of pumps forces the valve open and the mixture escapes through the In passing through the aperture und^r small aperture.

232

ICE

CREAMS AND ICES

high pressure the fat globules are broken up and distributed through the liquid. In the other type of machine the aperture through which the mixture passes is fixed and will not vary with the pulsations of the machine. The homogenizing

done by forcing the mixture through grooves which are arranged radially in discs. The fat globules are thoroughly
is

broken up

in passing

through

this rigid aperture.

The Progress Homogenizer.

more viscous and

Ordinary cream after passing through a homogenizer is gives a better bodied ice cream than cream which has not been so treated. The most attractive feature of this machine to the ice cream maker, however, is that

—

THE

ICE

CREAM FACTORY

233

a mixture of unsalted butter, skim milk powder, and water

can be made into cream by passing the mixture through
the homogenizer.

Cream which has been properly homogenized does not readily, and being more viscous than cream which has not been homogenized, is valuable alike for ice cream makchurn
ing and for whipping pui-poses.

The
ers,

emulser.

There are now a number of machines on

the market variously

known

as emulsers, emulsifiers, convert-

creamers, and cream makers which combine the butter

and milk serum so thoroughly as to prevent further sepA mixture containing the proper proportions of unsalted butter and milk after passing through an emulser has all the properties and appearances of fresh cream. In some of these machines the fat globules remain unchanged,
fat

aration.

Steam Nozzle-.

i— Adjustino Nut -Cone Holder

Discharge—
Cone Guides

I

I

LCOUPUINQ Clean Out Plug

sectional

view of Hauk's Emulser.

while in others quite a large percentage of them are broken
up.

The cream made by
is

these machines can be whipped,
as ordinary cream.

frozen, or churned the

same

The emulser
ice

one of the very recent adaptations to the cream business. Since these machines are less expensive

234

ICE

CREAMS AND ICES

than the homogenizers, they are therefore within the reach
of smaller concerns.

Emulsers are of two general types in the one the emulby forcing the ingredients through very In the other fine crevices by means of centrifugal force. type, steam is used in various ways. Hauk's emulser is one of the machines in which steam is used. Steam is discharged through a small nozzle into The ingredients are drawn into a tube, creating a vacuum. the emulser by the vacuum and forced with considerable pressure through the tube into a chamber, called a cone. The cone of the machine is made of specially constructed woven wire of fine mesh. The flow of the mixture through The agitation to the machine is retarded by this cone. which the mixture is subjected in passing through this machine is such that when it leaves the emulser the mixture is
;

sification is effected

completely emulsified.
ules are

A

considerable

number

of fat glob-

the fat

broken up by this machine. The extent to which globules are broken up will depend upon the steam
to

pressure.

The standard
trap
is

which the emulser proper

is

connected

contains a water trap of very unique design.

The water
is

so constructed that only pure, dry steam

allowed

to enter the emulser with the mixture.

The condensation

from the steam which enters the mixture amounts to about one pint in eight gallons of the finished product.
emulser.

The Dewitt and McCaddon converter To install and operate one of
more than 20

is

also a steam

these machines,,
If the

select a place as

near the steam line as possible.
feet

converter must be located
boiler,

from the
where the

the

steam pipe should be covered with asbestos.

Run

a three-fourths inch steam line to the point

; ;

THE
converter
is

ICE

CREAM FACTORY
fit

235

to be installed.

Put on a steam valve; reduce
the

the three- fourths inch steam line at this place to

three-eighths inch steam inlet on the
converter. On the top of the converter screw in a half inch " T " with

a

fourth

inch

side

outlet.

Use a
long

fourth inch syphon and a small steam

gauge.

Take a

i

inch

pipe

enough to elevate the cream into the cooler or vat and bend it in a semicircle. Screw one end of the pipe into the " T." On the other end place a straight i inch water or steam cock.
(9 in Fig. 90.) Below the i inch cock use inch pipe of any length needed to convey the

the full head of steam has been turned
on, partially close the water cock so that the pressure

gauge above the con-

% %

verter registers at least ten pounds.

With

this pressure the converter will

236

ICE

CREAMS AND ICES
The
valve

give good results.

may be

closed

still

more,
advise

making the gauge

register higher.

A

pressure as high as

22 pounds will do no harm.

The manufacturers

operating at about 15 pounds pressure. The operator will soon learn which gives the best results, as the pressure
varies according to the altitude of the place

where the conand the steam
the
cold water

verter

is

used.

All the connections

must be

air tight,

pressure not less than 80 pounds.
circulate through the

The gauge above
;

converter must register at least ten pounds

must

machine while

it is

in operation.

The

temperature of the emulsion should not exceed 130° F. The steam emulsers described above are quite different
the Cooksley

from the centrifugal machines. The DeLaval Emulser and Creamer are good representatives of the ma^
"--'

chines of the centrifugal type.

'

The DeLaval emulser
a
centrifugal
separator.

resembles
Instead
of
^.

'*

..i^sSSS'

THE
device.

ICE CREA]\[

FACTORY

237

a bowl, however, the emulser has a rotating, emulsifying

The

emulsifj'ing
steel discs

of

chambered

mechanism consists of a series mounted one upon another around
to be emulsified enters
is

a central feed shaft. the chambered discs.

The mixture
The

the machine through the feed shaft and

distributed to

centrifugal force in the emulser

discharges the mixture through the very fine crevices be-

tween the discs. The mixture through these small apertures.

is

emulsified

in

passing

UPP£lf OIJC-

-our LET

CHAMBCfi

_ai5 TR/BUTIfIC

Fig.

92.

The

fying

mechanism

emulsiof the

Cooksley Creamer.

trifugal emulsifier,

consists of a mixing vat, a cenand a cooler. The melting vat in which the mixture is prepared and pasteurized is elevated above the centrifugal machine so that the mixture flows by gravity
to the

The Cooksley Creamer

creamer and from thence to the cooler.

No pump

238

ICE
little

CREAMS AND ICES
piping
is

and but very
discs

required for these machines.
consists of

The emulsifying mechanism

two heavy

steel

held together by a lock nut.

This device rotates

at the rate of about 12,000 revolutions a minute. The mixture enters the emulser at the top and is distributed to the

chamber around the feed

shaft.

The pressure The
fat
is

within

the rapidly revolving emulser forces the mixture through

the small aperture between- the discs.

reduced to

small globules and evenly distributed through the milk serum.

Since the emulsers are

all

quite simple in construction
it

and can

easily be taken apart,

is

not a very

difficult

matter to clean and

sterilize the parts that

come

in contact
is

with the mixture.

The substance

to be emulsified

first

heated to a temperature of from 140 to 180 degrees.^ In other words, the mixture is pasteurized before it enters
the emulser.
it

If the

machine has been properly cared for

will

not be necessary to pasteurize the cream again.
to Prof. F.

According

W.

Bouska,
it is

in

preparing the mix-

ture for any of these machines,

best to put the desired

amount of butter

in the cold

milk rather than to add the

butter after the milk has for this precaution
acidic.
is

become quite warm.
is

The reason

that the butter
is

sometimes quite

If

such butter

placed in very hot milk, there

may

be sufficient acid present to cause a partial curdling of the mixture before the butter is evenly distributed. The
difficulty is easily overcome by allowing the butter and mix more slowly with the skim milk.

to melt

1 The temperature to which the mixture is heated may vary somewhat with the different emulsers. The manufacturers of the Cooksley Creamer recommend heating only to 140° F. because the mixture is held for a time before it is emulsified. For the DeWitt

& McCaddon Converter the temperature of the emulsion should not be over 130° F,

CHAPTER

XVIII

FACTORY MANAGEMENT
Within comparatively recent years the
ice

cream industry

has grown from a small caterer's business to a large factory system. Conditions and ideas are changing; new methods
are being tried out and adopted or rejected according to
their merits.
cess

The system

of

management

that brought suc-

and profit a few years ago will not prove satisfactory under present conditions. This transition from such an insignificant beginning to the present well organized and growing industry has been aided by the great improvements which have been made in ice cream machinery. The result of this improvement in methods is shown by the fact that the price of the manufactured product has been reduced while the cost of raw materials has actually increased. A factory equipped with old style apparatus can not compete on equal terms with a modern factory under present day The business methods followed have not in all conditions. cases kept pace with the improvements that have been made Even the best equipped facin machinery and equipment. efficiently without an up-tomost operated can not be tories which the actual costs of doing accounting in system of date
business are determined.

The use

of records for determining the cost of manufac-

turing, selling,

sufficient attention at the

managers.

and delivering ice cream does not receive hands of many ice cream factory There are two things to be accomplished by
239

240

ICE

CREAMS AND ICES

The product can be improved and kept more uniform, and losses can be detected and stopped or, at any rate, reduced. The uniformity of the product is an important factor This in itself is a sufficient in gaining and holding trade.
the proper use of records.

__^>

Fig. 93.

The Progress Drip Sa\er
that

for saving the milk

and cream

would otherwise be wasted.

Systematic improvement and dereason for using records. velopment comes only by determining what conditions give It is only by the use of records the most satisfactory results. Where such that the necessary data may be obtained. records are kept a desirable method may be duplicated and In the less satisfactory and wasteful methods detected.

FACTORY MANAGEMENT
ance of new help, making
sible
it

241

addition to this, the records furnish an index for the guid-

much

easier to take

on new

help and get them trained to the system with the least pos-

waste and inconvenience.
freezing record will show the conditions under which
is

A

the ice cream

frozen.

It will also indicate

the conditions

under which the best yields are obtained. The ice cream maker's report shown below contains about all the necessary information. Such a report is not made out for each freezer full but for each large batch of mix. Where one man takes care of the mixing and another handles the freezers, the responsibility is divided by using such a form as is shown here. The man who does the mixing fills in the first half of the form and then passes it on to the man in charge of
the freezing,

who
ICE

fills

in the last half of the report.

CREAM MAKER'S REPORT
Date
Stabilizers used
,

No
Kind of ice cream or sherbet Formula No Age of cream
Acidity

Per

cent, butter fat

Temperature of mix
Gallons of mix

Signed

Number
Swell

of batches from this

mix
gallons

Gallons of ice cream

made
per cent.
minutes.

Average time
of brine

to freeze

Temperature

degrees F.
:

Remarks

Signed.

242

ICE

CREAMS AND ICES
will

Other records should be kept which
sible to

make

it

pos-

determine the cost of the various operations.
satisfied in

The

manager should not be
as a

whole yields a certain

knowing that the factory profit. His aim should be to

make

the factory yield a fair profit with the least possible

waste of energy and material. Any one familiar with the business can devise a system which will eliminate many of the losses and reduce manufacturing costs.
If the business is

very large, the simplest
cost sys-

would be to employ an expert accountant and allow him to work out the details of the
solution of the problem

tem.

Ice

The forms shown on the following pages appeared in the Cream Trade Journal of July, 1912, and are reproduced
These forms are so simple that they

here by permission.

require no further explanation.

The costs of conducting the business may be grouped under four main heads. The cost of material, power, and refrigeration would be charged against making. The cost of advertising, ofHce expenses, and similar accounts would come under selling. The maintenance of horses or autos would be charged against delivery. The interest on the investment, depreciation, repairs, and similar items of expense may be charged against maintenance. The records that will be needed to furnish this information are a daily report of supplies taken into, and supplies taken out of the store rooms a record of- the amount of ice cream placed in the hardening rooms and the amount taken out. The difference between the amounts taken in and the amounts taken out will constitute the balances on hand at the close of the This balance should be carried forward to day's business. the next day's record. These various records when properly
;

244

ICE

CREAMS AND ICES
24

ENGINEER'S REPORT FOR

HOURS

M

19

to

M

FACTORY MANAGEMENT
ENGINEER'S REPORT FOR
24

245

HOVRS.— (Continued.)

Temperatures

How
What

long_
cause

Used

cyl.

No.
cyl.

Returned

No.

Supplies ordered.

246

ICE

CREAMS AND ICES
tell

kept will enable the manager to
factory.

at

any time what

it

costs

a gallon to manufacture and deliver the products of the

The
it

cost of delivery

is

too often far in excess of what

should be.

This end of the business

may be

kept well in

Fig. 94.

A

good type of Delivery

Wagon

for

heavy duty.

hand, however, by carefully checking each driver in and out.

A

form somewhat

like the

one shown on page 248

may be

used for the purpose.
time required for each

In addition to the information con-

tained on this report, provision
trip.

may be made

for reporting the

driver signs for the load

When a wagon goes out the taken. When he returns the shipThe
original copy re-

ping clerk signs for the load returned.

FACTORY MANAGEMENT

247

mains in the shipping book. The driver is given a carbon copy for his own protection. There are many factories in which there is no check of any sort upon the dehvery men. Such loose methods foster It requires a little more carelessness and even dishonesty. time to keep these records, but the reductions in cost due to

Fig. 95.

A

lighter Delivery

Wagon.
for extra time

increased efficiency will
in

more than compensate

keeping them.

Keeping track
from

of packing tubs.

In every factory

packing tubs are sent out that are never returned.
this source is

many The loss

sometimes quite large. The difficulty in keeping track of all these packing tubs causes considerable annoyance and no small loss of time. This is particularly

o
J=

;-<

o
"o CO

>

<
Ph

y
Pi

o u < w Pi u w u

FACTORY MANAGEMENT

249

true of the small factories that cater to a family trade and of factories that ship large quantities of ice cream to out
of town points. A weh planned system of checking outgoing and in-coming tubs will reduce the loss and annoyance to a minimum. The system adopted must be reliable and
so simple that
it

will require but little attention.

A

system

that

is

cumbersome and

requires very

much

time will soon

fall into disuse.

of the most common methods of by means of shipping tags with detachable stubs, a system which is quite satisfactory in factories with a large output. In this system a duplicating order book is used. The orders are taken in the office and sent to the shipping department to be filled. The shipping clerk fills out a shippping tag and hangs the tag and order upon a hook corresponding to the day of the week upon which the order must be filled. In this way advance orders are sure to be taken care of in due time. In the office or in the shipping department is a small case with 31 compartments which are numbered consecutively from i to 31. When an order is filled the shipping tag is attached to the tub. The stub is detached and filed in the compartment corresponding to the day of the month on which the order was When a packer is returned to the factory the tag is filled. detached and the stub belonging to the tag is removed from the compartment in which it was filed. The stubs remaining in the compartments represent the number of unreturned packing tubs. After about a week's time, if all the packers sent out on a certain day have not been returned, they should be collected. If any have been sent out of town, a post card to the person holding the packer will generally insure Since there are 31 compartments in this its prompt return.

Shipping tags.

One

checking packing tubs

is

250

ICE

CREAMS AND ICES

y

FACTORY MANAGEMENT
case, the stubs in

251

each day.

In this

in regular order.

may be checked over way the tubs are checked and recalled The principal objection to the system is
one compartment

that the tags are frequently detached
is

and

lost

before the tub
is

returned to the factory.

In such cases there
it is

of the returned packer, and

difficult to tell

no record from whom

the packer

may have come. Numbering the packing tubs will help to overcome this difficulty. The number of the packer may be recorded in the order book opposite the name of the person to whom
the tub

was

sent.

When

a tub comes back without a tag,

Fig. 97.

Showing

a

System of Numbering Packing Tubs.

the shipping clerk makes a

memorandum

of the number.

of the person returning the tub may be found number in the order book. Another way to tracing the by handle such cases is to file the memoranda away and refer

The name

to

it

whenever the stubs are checked over.

When

a stub

is

252

ICE

CREAMS AND ICES

found bearing the number of the packing tub, the stub is removed. The problems which we have been discussing have to do entirely with preventable losses and factory efficiency. Along with this policy of factory efficiency there must be When all the necessary arrangements selling efficiency. have been made to insure economical operation and good service, the next problem is to increase the demand for the product of the factory. Quality and good service speak for themselves, but these should not be depended upon
entirely.

The

public in general
reputation.
is

must know the

factory,

its

product, and

its

The value

of advertising

quite well understood

by

modern business men, but beginners must

learn that ad-

vertising pulls slowly and is therefore of little value to a " quitter." The advertising must be varied but uninter-

rupted in order that the public
the

may become

acquainted with

name and

brand.

When

it is

learned that one particular

brand stands for cleanliness and uniformly high quality, the results of an advertising campaign will become apparent. The methods by which a product may be introduced to Unique signs which the public are numerous and varied. take the eye and a catchy slogan are always valuable means An advertiseof calling attention to the goods advertised. ment may be unique or attractive, however, and yet be inA good ice cream effective because it is not suggestive.
advertisement must suggest eating to the reader of the advertisement.

ing which has been adopted by ing advertisement
advertising in that
differs
it

The paid reading advertisement is a method of advertismany plants. The paid readis

in the

from the ordinary newspaper form of regular reading

FACTORY MANAGEMENT
vertising

253

matter instead of the ordinary advertising form. Such adwhen properly written up is particularly valuable
at the opening of the season, or to call attention to

some

new specialty which is being introduced. The society column of the local papers

is

made

use of

by some manufacturers with very good results. The way in which this kind of advertising is conducted is by means
of personal or circular letters.

When some

social function

has been announced in the society column the person who has given or who is about to give the party is sent a letter
calling the person's attention to the particular factory,
its

equipment, and

facilities for

taking care of just such orders.

few timely suggestions could be offered in regard to the which might be supplied and which would be found appropriate for social occasions. If this method of advertising is handled tactfully the results will be found quite
specialties

A

satisfactory.

The various methods
results only

of advertising which have been

applied to the ice cream business

standard.

the public

may be relied upon to bring when the quality of the products are up to The public taste should be studied carefully and given what it demands. The winter season is

ordinarily slack, but the progressive manufacturer need not

up the plant if he will but enter the field with some The specialty and cater to the society or fancy trade. different demand kind of ice a summer and winter trades best adapted creams are to cream. The fancy molded ice winter months. the fall and catch the trade during Ice cream for special occasions is sure to draw trade. When one is catering to a high class trade it will be necesclose

sary to put out a greater variety of frozen products.
plain formulas used
in the

The

summer time

are not the kinds

254
to use

ICE
when one
is

CREAMS AND ICES
after the winter trade.

The unusual

and unique
sellers.

in composition, flavor,

and design are the best
should not be overconsider the small

looked.
special

The importance of the winter trade Many manufacturers do not
orders

worth bothering with. This is a wrong There is a decided policy upon which to operate a factory. advantage in continuous operation. The public becomes accustomed to dealing with a certain firm. If the service
is

at all satisfactory, customers are not likely to discontinue

their patronage without cause.
close its doors or the

The factory which does not manager who does not abate his efforts during the ordinarily slack months is sure to begin the next

season with an advantage over his competitors. This advantage is due partly to the fact that he holds his customers from season to season and helps to create a larger demand for frozen dafnties, increasing in this way his hold on the
public.

The
it

uninterrupted operation also makes

it

possible

to keep a certain

number

of steady men.

When

the season

opens

will not

be necessary to pick up and train an entire

new

force.

CHAPTER XIX
BY-PRODUCTS AND SIDE LINES

The question of by-products and side lines deserves the very serious consideration of the ice cream manufacturer. In a business such as ice cream making it is very important
varies between such

demands of the customer be met. The demand wide limits that on some occasions there is a shortage of milk or cream and at other times there is The question is what to do with this surplus. a surplus.
that all

Many
line
it is

factories have
in

found

it

profitable to

carry a side

which works

with the other factory operations.

Since

so important that the factory should have an abundant

supply of sweet cream and milk at the times of heavy

demand, it is obviously an advantage to buy more than is needed under ordinary conditions, provided the surplus can
be disposed of profitably.

The secondary products or side handled by an ice cream factory should be such as require but very little additional outlay of capital to propAny product that can be so handled will erly carry them. prove profitable in more ways than one.
profitable side line.
lines

A

Other dairy products may be handled along with ice cream quite readily and are of particular importance to Since a well equipped ice the ice cream manufacturer. cream factory contains practically all the apparatus necessary for handling milk and cream, the sale of these commodities can be worked in with the regular ice cream busi255

256

ICE

CREAMS AND ICES

ness and will afford an outlet for the surplus milk and cream. Advantages in handling a side line. Aside from the

Fig. g8.

The TurnbuU

Ice

Cream Cone Machine.
side lines,

direct profit derived

from the by-products and

there

is

the added advantage of continuous operation of

the factory.

The

addition of one or

more secondary prod-

BY-PRODUCTS AND SIDE LINES
ucts to the output of the factory

257

a certain
to

makes it possible to retain number of regular men, so that it is not necessary shut down during the season when there is little demand

for ice cream.

A

plant that

is in

continuous operation has

a decided advantage over competing plants that are not so operated. With a part of the crew well trained it will be much easier to get into shape for the work of the busy Then, too, advantage can be taken of every demand season.
for ice cream during the winter months.

This would not

be possible
the winter.

if

the factory were operated intermittently during

Butter, as a rule,

is

the least profitable of the

dairy

products to be handled by the ice cream maker located in

where rental and other expenses are apt to be For example, if 3.5 per cent, milk costs $1.50 a 100 pounds, when the butter fat price for sour cream is
a large
city,

very high.

pounds of milk for which the ice cream be worth only 98 cents at the ordinary market price, a loss of 52 cents for each 100 pounds of milk. The profit derived will, of course, depend upon the price that must be paid for butter fat and the manner in which the product is disposed of. There is, however, a special trade that is not reached by the majority of butter factories. This is the trade the ice cream maker who finds himself forced to make butter should endeavor to reach. The cream may be too sour for ice cream making, but can very easily be made up into butter of superior quality which should command the very highest market price. Butter for homogenized cream. With the introduction of the homogenizer for making up cream from butter and skim milk or milk powder there has arisen a demand for
28
cents, the 100

maker paid $1.50

will

258

ICE

CREAMS AND ICES
Some
in cold "

unsalted butter of highest quality for this purpose.
factories

buy unsalted

June Extras " and hold

it

storage for use during the rush season. Where factories have an occasional over supply of sweet cream that must be disposed of, it might be profitable to churn it and hold the butter in an unsalted condition in cold storage for use as soon as there is a demand for an extra supply of

cream.

Sweet cream

is

one of the most profitable forms in which

to dispose of the surplus

cream or a portion of

it.

About

14 pounds of 25 per cent, cream will be obtained from each 100 pounds of 3.5 per cent. milk. This amount of cream,
at

20 cents a

pint, is

worth $2.80; at 15 cents a

pint,

it

would bring

$2.10.

In addition to the cream, there would

be about 85 pounds of skim milk to be disposed of. At 5 cents a gallon, the skim milk is worth about 50 cents, but if it is made up into fermented milk it would bring about
pounds.

8 cents to 10 cents a gallon or 80 cents to $1 for the 85 Another form in which skim milk may be dis-

posed of to good advantage,

is

as cottage cheese or soft

cream cheese. Eighty-five pounds of milk yield about 12 pounds of cheese, which, at 8 cents to 10 cents a pound,
gives a gross return of $0.95 to $1.20.

Skim

milk, fermented milk, cottage cheese,

and butter-

milk are among the dairy products that are always handled as side lines in connection with some other business. That
is

to say, they never constitute the

main output of a

plant.

found these profitable. Under favorable conditions, there is no reason why they could not be handled profitably by ice cream makers. Since many factories have a surplus of skim milk to be disposed of, fermented milk is probably one of the

ISuttermakers and whole milk dealers have

BY-PRODUCTS AND SIDE LINES
best side lines that can be carried.

259

equipment

will be required

Very little additional and no extra expense need be

involved for delivery.

Fermented milk.

vestigation of the therapeutic value of buttermilk

Within recent years considerable inand other
Various

forms of fermented milk has been carried on.
cians in the treatment of intestinal disorders

kinds of fermented milk have been recommended by physi-

and considerfor these

able quantities of fermented milk and buttermilk are used
in

hospitals.

As

a natural

result,

the

demand

Fig. 99.

Types of Single Service Milk Bottles may be used for milk,
cream, or fermented milk.

products has increased considerably. This condition should be made use of by the ice cream factories. Since the raw
material
is

available in

many
it

factories

and the demand for

the product already exists,

only remains for the ice cream

There are a nummay be made from on the market under some milk. Some of these are placed are fundaof them, however, Most special trade name. fermentation. lactic mentally some form of a
factory to produce a satisfactory article.

ber of special fermented preparations that

26o

ICE

CREAMS AND ICES
The most common fermentation
is is

Lactic fermentation.
occurring in milk
is

the lactic acid fermentation, which
lactic acid
is

brought about by the

group of bacteria.
is

This

the same bacteria that

used in making starter and in
the byis

cream ripening.

Buttermilk, properly speaking,

churned for buttermaking. Where good, clean flavored cream is churned, the buttermilk will have a rich, mildly acid flavor. Much of the buttermilk now sold in the cities is off flavor and of doubtful purity and quality. To secure an abundant supply of buttermilk
in

product obtained when cream

fresh

condition and

free

from objectionable
specially

odors, large quantities are

now made by churning

soured skim milk.
quite the
it

The

resulting product does

not have
prefer

same

flavor as the true buttermilk but

many

by churning cream. Prepared buttermilk. To make buttermilk by the method just mentioned, either whole milk, skim, or partly skimmed milk may be used. The buttermilk has a richer and more pleasing flavor where whole milk is used instead of skim milk. The milk should be pasteurized and cooled to 70° F., inoculated with a good starter, and allowed to stand until begins to thicken. The soured milk should then be it placed in a churn and churned for 20 to 30 minutes to break up the curd into very fine particles. Since butterrrailk obtained by churning cream contains all the milk constituents except fat, it does not differ in composition from the prepared buttermilk made by fermenting pasteurized skim milk with special cultures of bacteria. In comparison with the average buttermilk from churned cream that is offered for sale in the large cities, this prepared buttermilk is decidedly superior from the sanitary standpoint This is the product frequently as well as in body and flavor.
to the buttermilk obtained

BY-PRODUCTS AND SIDE LINES
put

261

upon

the

market

under

the

name

of

" Lactone."

lactic acid bacteria,

In addition to the ordinary cultures of one may obtain cultures of special organisms for the manufacture of fermented milk. Many of these different cultures no doubt contain organisms nearly or quite identical with the Bacillus bulgaricus, which is the generally adopted name of the organism which produces a very characteristic fermentation and gives a product of very superior quality. This product, or a fermented milk nearly resembling the fermented milk made from B. bulgaricus, is frequently put upon the market under various names such Some as Bulgarian buttermilk, Lactone, Fer-mil-lac,^ etc. processes are patented and may used only of these be by
permission of the patentee.

Special cultures.

Yoghurt

is

the general

name
S.

given to this class of fer-

mented milk by the U.

Bureau of Animal Industry.

The
the
cific

older name of Bacterium caucasicum is used instead of more common name of Bacillus bulgaricus for the spe-

organism.^

Bulgarian cultures.
ture of fermented milk.

There are several decided advan-

tages in using the cultures of B. bulgaricus in the manufac-

The Bulgaricus cultures have a tendency to produce a more slimy curd which does not whey off like the natural or the prepared buttermilks in which only lactic acid organisms are used. The slimy
curd produced by the Bulgarian bacteria is not so satisfactory when used alone, but in combination with the ordinary lactic acid fermentation a milk having a very smooth creamy consistency and a very mild and pleasing flavor is
produced.
1 2

Process patented. Circular 171, Bureau of Animal Industry.

262

ICE

CREAMS AND ICES
The ordinary
lactic acid

The method

of manufacture.

bacteria and the Bulgarian bacteria can not be

grown

to-

gether in the milk at the same time, because of the different
conditions of temperature required by the

two organisms.
is

The most

satisfactory

method of procedure

to pasteurize

two batches of milk. Cool one to 70° F. and inoculate it with a pure culture of lactic acid bacteria. Cool the other batch of milk to 100° F. and inoculate it with a culture of Bulgarian bacteria or some -similar organism and allow the two batches to ferment for 24 hours at the temperature Both batches are then mixed at which they were inoculated. and poured into a churn and churned for 15 or 20 minutes. This action breaks up the curd and the two cultures are thoroughly mixed. The more tenacious curd of the Bulgarian organism prevents the milk from wheying off and gives a

creamy consistency to the finished product. Marketing fermented milk. These special milk preparations are very popular and there should be no difficulty encountered in creating a larger demand for them. The milk should be put up in quart bottles. The caps used should contain some neat and appropriate derich

sign
will

or name.

A

little

advertising

soon get the public acquainted
ice

with the product and the
outlet for the surplus milk.

cream

factory will be assured of a profitable

Cottage cheese.

The method
is

of

Fig. 100.

A

neat Con-

making cottage cheese

very simple,

°^

°

^^^

Cheese

but the quality of the product as found

on the general market is rather variable. When properly made, cottage cheese has a very smooth texture, free from lumps, and a rich, clean acid flavor, resembling ripened

:

BY-PRODUCTS AND SIDE LINES
cream.

263
is

The average

composition, according to Publow,

as follows

Water
Proteids

72.0%
20.0
5.5

Sugar, lactic acid, etc

Mineral matter

2.5

100.0%

A

study of the above table shows the high nutritive value

made from skim milk. Its quality will be greatly improved and its food value increased by the addition of a little sweet cream.
of cottage cheese

Methods

of manufacture.
is

The

simplest

method of mak-

about 10 to 15 per cent, of good starter to raw skim milk at 70° F. and allow
ing cottage cheese
to curdle.

as follows:

Add

it

When

it is

into fine particles
utes.

and heat

evenly curdled, break up the curd to 104° F. and hold for 15 min-

bag and hang it up to mass of curd should be salted at the rate of one ounce of salt to eight or ten pounds of curd. A pound of sweet cream to ten pounds of curd may The curd should then also be added to give a richer flavor. be worked thoroughly to give a smooth, uniform texture and The cheese should then be packed to distribute the salt. This in one pound containers and placed in a refrigerator.
into a muslin

Pour the curd

drain.

When

dry, the

cheese does not require curing but

is

ready for use at once.

More uniform

results will be obtained

by pasteurizing the

skim milk before adding the starter. amount of starter used, the milk can be

By

regulating the
it

set so that

will

be

ready for heating and draining at about the same time each In this way the process can be so timed that the day.

264

ICE

CREAMS AND ICES
if

work

of caring for the cheese need not interfere with other
;

operations

however,

a high class trade

is

to be served,

a high class product must be produced and each step of the process must have proper attention. It is not customary to make this cheese from whole milk, as there is a very heavy loss of fat in the whey. The better way is to make it from skim milk and add the fat in the form of sweet cream after the curd has been drained. Instead of a muslin bag a vat strainer with perforated A sides and bottom may be used for draining the curd.
piece of ordinary cheese cloth
is

spread over the strainer

before the curd

is

put

in.

From 15 to 20 pounds of cottage cheese will be obtained from 100 pounds of skim milk, depending upon the amount of moisture retained by the curd. Care should be taken not
to allow too
this gives

much

of the

whey

to

remain in the curd, as

a sour, sticky cheese.

The amount of moisture

retained may be controlled by the heating process. Longer and higher heating gives a drier curd. When put up in a

neat package, cottage cheese

sells for 8 to 10 cents a pound. Neufchatel cheese. This is the name of a soft French cheese cured by means of a mold. The method by which it is made in this country differs considerably from the original method and closely resembles the method for making cottage

cheese.

Method

of manufacture.

Whole milk

is

pasteurized and

cooled to 75° F. and about 20 per cent, of a good starter

added and mixed

well.

Add

rennet extract at the rate of

two ounces

to 1,000

pounds of milk.

The
its

rennet extract

volume of cold water and thoroughly mixed with the milk. Cover the yat of milk and allow it to stand quietly for one to one
should be diluted with about five times

BY-PRODUCTS AND SIDE LINES
and one-half hours or
firm.
until

265

evenly coagulated and quite

The curd should be

cut into small pieces by

means

of cheese knives and then poured into a strainer lined with

cheese cloth and allowed to drain until
expulsion of the
of light

it is quite dry. The whey may be hastened by the application pressure. The curd should then be salted at the

rate of one ounce of salt to eight
until

very smooth and free from lumps.

pounds of curd and worked It is then packed

in containers the

up

in

round

rolls

same as cottage cheese, or it may be put and wrapped in parchment paper and tin
is

foil.

Cream cheese
cream

made by

the same process, using a thin
is

testing about ten per cent, butter fat, but as there

a very heavy loss of fat by this method, it is more economical to use whole milk and add stifficient rich cream to
give the desired flavor.

cheese

Fancy soft cheese.^ From the Neufchatel and cream made by the above process, a number of fancy soft cheeses may be made by the addition of nuts, peppers, olives,
etc.

Sandwich nut cheese is made by adding four or five ounces of blanched almonds and walnuts, finely ground, to
ten pounds of cream cheese.

Pepper cream cheese is made by adding one-fourth to one-half pound of red peppers to ten pounds of cream
cheese.

Olive cream cheese is made by adding the meat of about two or three dozen olives to ten pounds of cream cheese. The above products may be found valuable to those who During the winter desire to work up a winter trade.

months the bulk of the
3 "

ice

cream sold

is

used at social

Fancy Cheese

for

Farm and

Factory,'' Cornell Bulletin, 370.

266
functions.

ICE
Fancy

CREAMS AND ICES
creams are popular on such occasions.

ice

Some

fancy special product like those given will often

prove an effective means of drawing this winter trade. Whipped cream. This is a product that belongs properly with the ice cream business, although it is not a frozen
product. In every town of any size large quantities of whipping cream are used both by confectioners and houseOwing to a lack of proper facilities, lack of knowlwives. edge, or both, much difficulty is sometimes experienced in whipping the cream. With all the facilities for cooling and handling the cream, this work could easily be taken care of Whipped cream is a term applied in the ice cream factory. to cream that has been beaten to a stiff froth by rapid agitaIn the whipping process a tion at a low temperature. considerable volume of air is incorporated with the cream. The finished product should be light and smooth but must have sufficient body to enable it to stand up well. The most important factors affecting the whipping qualiA thin cream ties of cream are richness and temperature.
is

not sufficiently viscous to hold the air incorporated in
is

the whipping process and the temperature
is

apt to churn, particularly

if

not very low.

On

an average the cream

should contain 30 to 35 per cent, of butter fat, but even this cream will not whip unless it has been thoroughly
chilled

for

and held at a temperature some time before whipping.
well

of not

more than 40°

F.

It is

pasteurized cream,
swell as
chilled

known to the average ice cream maker that when used in making ice cream, will not much as raw cream unless it is first thoroughly

order to restore
crea}Ti.

and held at a low temperature for some time in its viscosity. The same is true of whipping Greater difficulty is experienced in whipping pas-

BY-PRODUCTS AND SIDE LINES

267

teurized cream unless special precautions are taken to age or ripen it. No attempt should be made to whip it at temperatures over 40° F.

According to experiments conducted by the Maryland some years ago, it seems that acidity also affects the whipping qualities of cream: The following extract is taken from Bulletin 136 of the Maryland station. " The older the cream up to the point of separation of whey from clabber the better it whipped. For this reason gravity cream of the same fat content whipped better than
station

fresh separator cream, 12 hours usually being required to

This was accompanied by a development of 0.2 to 0.3 of lactic acid. Samples of cream were also whipped with and without commercial lactic acid sO' as to
raise.

per cent,

overcome any changes which would occur were the cream
allowed to remain at various temperatures while lactic acid increased naturally. In every instance the cream to which

commercial lactic acid had been added whipped in less time and produced a more dense foam than did that to which no acid had been added. " Lactic acid, either natural or commercial, at low temperatures affected a gelatinous consistency of the casein

and albumen of the cream, which rendered
holding a considerable quantity of
ping.
" In the following tablet
air,

it

capable of

thus facilitating whip-

each sample of cream has been

held at 45° F. for two hours.

Here the
cent,

effect of

lactic

acid proved to be of greater importance than that of the
fat

content

.

.

.

0.3

of one per

of

acidity

is

the

maximum which cream may
sour taste."

contain without acquiring a
viscogen,

Viscogen.

A

substance

known

as

which

is

I

268

ICE

CREAMS AND ICES

u <
><

> O w o
p-l

o H
P W
Pi
I

—

a
w w

BY-PRODUCTS AND SIDE LINES
made from
substance
is

269

a solution of sugar and lime water,

times used to restore the viscosity of cream.
not in

is someWhile this any way harmful, cream in which it

has been used should be so labeled.

In case the consumers have been accustomed to buying the whipping cream and doing the whipping themselves it

may be
line.

necessary to work up the trade for this product, but
it

once established,
ers

should prove a very profitable side
in ice

The whipped cream can be packed

cream pack-

for delivery and will stand up well

when properly

packed.

CHAPTER XX
ICE

CREAM AS A

SIDE LINE IN

THE LOCAL CREAMERY

According to a recent report of the Bureau of Animal many of the small creameries have taken up the manufacture of ice cream as a side line. The plan has, in many cases, proved highly satisfactory. However, before a small creamery company undertakes the manufacture of ice cream, local market conditions and demands, as well as the adaptability of the factory and its location, must be
Industry,
carefully considered.

Local conditions.
of ice cream.
If the

In a

tants there should be a ready

town of 1,200 or 1,500 inhabimarket for a limited amount
is

surrounding country

well settled,

or

if

there are a few smaller towns within a reasonable dis-

tance, the prospects of securing a ready
in

market for ice cream good to warrant the installation of the necessary machinery for the manufacture In a general way, howof ice cream in the local creamery. ever, it is safe to say that unless a market can be found for at least 20 or 30 gallons of ice cream a day during the summer, it will scarcely pay a small local concern to engage
paying quantities are
sufficiently
in the business.

Advantages of
creameries find
it

ice

cream

as a side line.

Many

small

difficult

to compete with larger creameries

in the general butter market.
it

The keen competition makes

necessary to stop

all

waste of power and labor and at
270

ICE

CREAM AS A SIDE LINE

271

the same time secure a market for the products of the
factory at a fair price.

Under many
and greater

conditions ice cream as a side line will

prove to be the best means of securing greater efficiency
profit

direct returns

from the factory. In addition to the from the sale of ice cream, there will be the

Fig.

loi.

Machinery for the manufacture of butter and
in

ice

cream

a small creamery.

indirect returns in the

form of greater popularity and greater

prestige accruing to the local concern, provided the business
is

properly handled.

There will be many possibiHties for expansion and improvement open to the creamery that manufactures ice cream There is an .opportunity to put into for the local trade.

272
effect a

ICE

CREAMS AND ICES

can be paid for good cream.
effect

system of cream grading in which a special price This in itself will have a moral
all

possible to secure a better grade of
ter

and will make it cream from which a betgrade of butter can be made. Once the creamery has
upon
of the creamery patrons,
its

established a reputation for the quality of

products the

matter of competition from larger concerns fades into insig-

Fig.

I02(.

The Floor Plan

of a combined Factory.

Butter and Ice Cream

nificance.

Where

a creamery has established
its

its

reputation

which should be known by for the quality of known good quality of the butbrand, the some particular the ice cream. The ice cream should bear sell ter will help butter, since the the public will naturally brand as the same high quality. The creamery manbrand with that associate ager must be sure, however, that the ice cream turned out is of good quality, otherwise the good qualities of one product
butter,
'

ICE
when used
eventually
itself.

CREAM AS A SIDE LINE
all

273

to sell another product of inferior quality will

work against

the products and the concern

New

problems to be dealt with.
it

Although the advanthat there will be

tages in the manufacture of ice cream in the local creamery are great,

must

also be

remembered

many new problems
tition

is the compecream factory. In many respects the local creamery will have a decided advantage, but the manager must appreciate and use these advantages. Competition in selling. In point of salesmanship, the large specialized ice cream factory will usually have the advantage over the local creamery. There is no reason, however, why the creamery man cannot learn much from his larger competitor and even adopt his best methods of selling. One of the, points of advantage possessed by the manager of the local plant lies in his more intimate knowledge of local conditions and demands. If he will take the pains to study these local demands and make use of his

to solve.

One

of these

from the

specialized ice

personal influence with the consumers, the competition of
the larger plant can easily be met.*

Competition in buying. In the matter of buying, the creamery has a decided advantage, as it is already in touch with a large number of cream producers. It is not such a difficult matter for the creamery to secure an abundant supply of sweet cream at a price only slightly in advance
of the price paid for butter fat for churning.
to this, the creamery has an outlet in the

In addition

form of butter

for

all

the cream which

it

may

buy.

Since the price paid

for sweet

cream

is

only slightly higher than for regular
loss,

churning cream, the factory does not sustain a
a small surplus of sweet cream be purchased.

should

274

ICE

CREAMS AND ICES

Additional equipment. The cost of equipment may be anywhere from $200 to $1,000, depending upon the volume
of trade to be taken care of. In the smaller concerns the manufacture of ice cream will prove profitable and advantageous only where the cost of the extra equipment is not great and no extra help is required. To begin with, a ten-gallon tub freezer may be used and
will take care of the trade until the business has increased

Fig.

103.

Showing

the complete equipment for a small ice factory.

cream

sufficiently to

a more improved type.
vat, extra pulleys,

warrant the installation of a larger freezer of An ice crusher, probably an extra

and extra belting, and a number of ice cream packers of different sizes will complete the equipment. It is assumed, of course, that the factory already has an ice house or mechanical refrigerating system which can be adapted to the needs of the ice cream business with
but
little

addition or alteration.

ICE

CREAM AS A SIDE LINE

275

The following quotation from Circular No. 188 of the Bureau of Animal Industry gives some idea of the profits obtained by the creameries of this country engaged in the manufacture of ice creams. " The average cost of making a gallon of ice cream is reported by them to be about 45 cents, and the same reports show the average wholesale selling price to be about 87 cents, leaving a margin of 42 cents a gallon. " The profits from the manufacture and sale of ice cream are clearly brought out by the following example: 100 pounds of 18 per cent, cream are equal to 12 gallons, which
with 66 per cent, overrun (swell) will produce 20 gallons of
ice
if sold for 87 cents a gallon will amount to Allowing that sugar and flavoring for this amount costs $1.40, there is left $16 for 18 pounds of butter fat

cream, and

$17.42.

used.

On

this basis, the butter fat sells for 88.8 cents a

pound.

The same amount

of butter fat

made

into butter

with a 21 per cent, overrun would produce 21.78 pounds of butter, and if sold for 31 cents a pound (average price for

New York
cents a

extras, 1910)

would amount

to $6.75 or 37.5
in favor of ice

pound for butter

fat.

A

comparison of these items

shows a difference of 51.3 cents a pound
cream.
"

The

special

equipment necessary for the average cream-

ery to manufacture ice cream consists of freezer, ice crusher,

holding cans, and hardening vat, and need not exceed $300 in cost. Such an outlay will often be paid for in one
season and a substantial suqjlus remain from the profits of
this

branch of the business."

APPENDIX
Table
I

Showing the Amount of Skim Milk, 3 Per Cent. Milk, 3.5 Per Cent. Milk, or 4 Per Cent. Milk to Add to 100 Pounds of Cream to Reduce the Test to 18 Per Cent.
Test of

cream

to

he standardized

APPENDIX

277

Table

II

Showing the Amount of Skim Milk, 3 Per Cent. Milk, 3.5 Per Cent. Milk, or 4. Per Cent. Milk to Add to 100 Pounds of Cream to Reduce the Test to 20 Per Cent.
Test of

cream

to

be standardized

278

APPENDIX

Table
Shoiving the

III

Amount of Skim Milk, 3 Per Cent. Milk, 3.5 Per Cent. Milk, or 4 Per Cent. Milk to Add to 100 Pounds of Cream to Reduce the Test to 25 Per Cent.
to

Test of

crcmn

be stand-

ardizcd

APPENDIX

279

Table IV
Showing the Amouut of Skim Milk, 3 Per Cent. Milk, 3.5 Per Cent. Milk, or 4 Per Cent. Milk to Add to 100 Pounds of Cream to Reduce the Test to 30 Per Cent.
Test of

28o

APPENDIX

Table
Shozving the

V

Amount of Skim Milk, 3 Per Cent. Milk, 3.5 Per Cent. Milk, or 4 Per Cent. Milk to Add to 100 Pounds of Cream to Reduce the Test to 35 Per Cent.

Test of

APPENDIX
Table VI
Showing Per

281

the Amount of Skim Milk, 3 Per Cent. Milk, 3.5 Cent. Milk, or 4 Per Cent. Milk to Add to 100 Poitnds of Cream to Reduce the Test to 40 Per Cent.

Test of

282

APPENDIX

Table VIII
SlioK'itic/ the
U'liicli Cream and Sl^iin Milk, Per Cent. Milk, or 4 Per Cent. Milk Must Be Mi.ved to Make 100 Pounds of 15 Per Cent. Cream

Proportions

in

3

Per Cent. Milk.

3.5

APPENDIX

283

Table IX
Showing the Proportions in Which Cream and Skim Milk, 3 Per Cent. Milk, 3.5 Per Cent. Milk, or 4 Per Cent. Milk Must Be Mi.red to Make 100 Pounds of 18 Per Cent. Cream

284

APPENDIX

Table

X

Showing the Proportions in Which Cream and Skim Milk, 3 Per Cent. Milk, 3.5 Per Cent. Milk, or 4 Per Cent. Milk Must Be Mi.vcd to Make 100 Pounds of 20 Per Cent. Cream

APPENDIX

28s

Table XI
Showing the Proportions in Which Cream and Skim Milk, 3 Per Cent. Milk, 3.5 Per Cent. Milk, or 4 Per Cent. Milk Must Be Mi.vcd to Make 100 Pounds of 25 Per Cent. Cream

286

APPENDIX

Table XII
Sliozviiig the

Proportions in JJliich Cream and Skim Milk, Per Cent. Milk. 3.5 Per Cent. Milk, or 4 Per Cent. Milk Must Be Mixed to Make 100 Pounds of 30 Per Cent. Cream
3

^s

APPENDIX

287

Table XIII
Showing the Proportions in Which Cream and Skim Milk, 3 Per Cent. Milk, 3.5 Per Cent. Milk, or 4 Per Cent. Milk Must Be Mi.ved to Make 100 Pounds of 35 Per Cent. Cream

288

APPENDIX

Table

XIV

Modification Table for Use in Ulaking Approximately Ten Gallons of Ice Cream ^
Quality
desired

APPENDIX

289

Table
For Use
in

XV

Shozving

Making Approximately a Gallon of Ice Cream, Amounts of Cream and Skim Milk Needed to Make 4 Pounds of Fluid Cream Before Freezing. The Figures Represent Pounds or Pints of the Different
^

Materials
Quality desired

PREPARATION AND USE OF VISCOGEN
The method
of preparing viscogen as given in Bulletin
"
:

Two and 54 of the Wisconsin station is as follows a half parts, by weight, of a good quality of cane sugar (granulated) are dissolved in 5 parts of water; and one part of quick lime gradually slaked in three parts of water. The milk of lime should be poured through a wire strainer to remove coarse, unslaked particles and then added to the sugar solution. The mixture should be agitated at frequent intervals and after two or three hours allowed to settle until the clear supernatant fluid can be siphoned off." Method of using viscogen. Both raw and pasteurized cream contain small amounts of lactic acid. In using viscogen, great care must be exercised not to add too much because even a slight excess of viscogen will give the cream The safest method of procedure a bitter and soapy flavor. is to determine the amount of viscogen necessary to neutralize the acid in a definite amount of cream and from this determine the amount necessary for the whole batch to be treated. The cream must not be completely neutralized, so one-half to two-thirds of the amount of viscogen necessary for complete neutralization will be sufficient to restore the viscosity to. the cream. Babcock and Russell suggest the following method for determining the amount of viscogen to add. By means of a graduated pipette or burette find the number of cubic centimeters of viscogen needed to neutralize the acid in a pound of cream. Multiply the number of cubic centimeters of viscogen used for one pound of cream by the weight of the cream to be treated and find two-thirds of the product, which will be the number of cubic centimeters of viscogen to add.
290

—
APPENDIX
:

;

291

I

Example If it requires 4 ex. of viscogen to neutralize pound of cream, and there are 100 pounds of cream to

4 ex. ^400 c.c. of viscogen to neu100 pounds of cream. But the cream should not be completely neutralized consequently, the amount of viscogen to add to 100 pounds of cream to restore the viscosity will be 2/3 of 400 c.c. or 267 c.c. Larsen and White suggest the use of a smaller quantity
be treated, then 100
tralize

X

;

of cream for titration and make the necessary calculations by the following method. Assuming that it requires 0.6 c.c. of viscogen to neutralize 25 c.c. of cream, the amount of viscogen needed for say 800 pounds of cream would be 35 :o.6 :8oo :x or 13.7 pounds of viscogen. Half this amount is sufficient to restore the viscosity of the cream
:

therefore,

-:

~

= 6.8 pounds of viscogen.

Caution. In many States the laws prohibit the addition of any substance to milk or cream, either for the purpose of neutralizing the acidity or for restoring the viscosity, It has been suggested unless the product is so labeled. that the term " visco-cream " be applied to cream which has been treated with viscogen.

TO CALCULATE THE SPEED OF PULLEYS Let D ^ the diameter of the driving pulley. R = speed in revolutions per minute,
d^the
r

diameter of the driven pulley,
in revolutions

=^ the speed of the driven pulley
per minute.

Then

D X R=d X

r.

I. To calculate the speed of a driven pulley, multiply the diameter and the speed of the driving pulley and divide the product by the diameter of the driven pulley.

2. To find the required diameter of a driven pulley when the speed is known, multiply the diameter and the speed of the driving pulley and divide the product by the speed of the driven pulley.

DXR_^
r

Taking the same conditions as given above, the calculations would be as follows

Example:

18

X
300

100

=

mches.

the required diameter of a driving pulley speed, and the speed and diameter of the driven pulley are known, multiply the speed and the diameter of the driven pulley and divide the product by the speed of the driving pulley.
3.

To

find

when

its

dXr
R

=D

Example: If a 6-inch pulley must' run 300 revolutions per minute, what size driving pulley will be required if the main shaft runs 100 revolutions per minute?

^X3°°= 18
100
4.

inches.

To

calculate the speed of a

main shaft when the speed

and diameter of the driven pulley and the diameter of the driving pulley are known, multiply the speed of the driven pylley by its diameter and divide the product by the diameter
of the driving pulley.

dXr
D

=^

:

APPENDIX

293

Example: How fast must an 18-inch pulley run to drive a 6-inch pulley at the rate of 300 revolutions per minute?
6

X —

r 300 =^ 100 revolutions per mmute.
,
.

SANITARY CODES
The following rules and regulations are reproduced here as suitable guides for those who are interested in the production of clean, wholesome ice cream.

New York

Sanitary Code.

sociation of ice is as follows
I.

cream inanufacturers of

The code adopted by the asNew York State

All factories or shops shall be open to the public at

all

times.

II. Work rooms must be thoroughly clean and shall be well ventilated and well lighted to the end that there shall be no dark or concealed corners where rubbish or dirt may accumulate. III. The sidewalls and ceilings of all work rooms shall be well plastered or tiled or ceiled with metal. If plastered or ceiled with metal, they shall be kept well painted with oil paint to the end that they may readily be cleaned and they shall be kept clean at all times. IV. The floors of all work rooms shall be impermeable and be made of cement, tile laid in cement, or of other suitable non-absorbent material which can be flushed and washed clean with water. Floors shall be sloped to one or more drains which must be properly connected with the sewerage system. V. Store room for materials shall be kept clean and free from objectionable odors. VI. Doors, windows and other openings of every work room shall be screened during the fly season, and all work rooms and store rooms shall be kept free from flies at all seasons of the year.

294
VII.

APPENDIX
All factories or shops shall have convenient toilet

rooms separate and apart from the work rooms, and no toilet room shall be within or connected directly with a work room either by a door, window or other opening. The floors of the toilet rooms shall be of cement, tile or other non-absorbent material, and shall be kept clean at all Toilet rooms shall be furnished with separate times. ventilating flues or pipes, discharging into soil pipes or on the outside of the building in which they are situated. Lavatories and washrooms shall be adjacent to toilet rooms and shall be supplied with soap, running water and clean towels, and shall be maintained in a sanitary condition. Work room employees beginning work and after visiting toilet room shall wash their hands and arms thoroughly in
clean water.

VIII. No person shall be allowed to live or sleep in any building used as a factory or shop, unless the factory or shop is separated by impervious walls, without doors or windows or other openings from the parts of the building used for living or sleeping purposes. IX. No horses, cows or other animals shall be stabled or kept in any building where ice cream is made, unless the factory or shop is separated from the places where the horses, cows or other animals are stabled or kept by impenetrable walls without doors, windows or other openings.

X. No person suffering from an infectious disease, which can be transmitted through ice cream, shall be employed in an ice cream manufacturing plant. XI. All work room employees shall be clean in person at all times and shall wear clean washable clothing and They shall not touch the product with their hands caps. Employees may be specially designated to at any time. cut and wrap brick ice cream and to fill fancy molds, and as this work necessitates some handling of the product, such employees must be scrupulously clean and wear clean, washable clothing and caps. XII. All wagons, trucks, drays, cans and tubs, plat-

APPENDIX
forms and racks
readily cleaned,
shall be so constructed that they

295

may

be

XIII.

and they shall be kept clean. Suitable means or appliances shall be provided

for the proper cleansing or sterilizing of freezers, vats, mixing cans or tanks, piping and all utensils used as containers for ice cream, and all tools used in making or the direct handling of ice cream, and all such apparatus, utensils and tools after use shall be thoroughly cleansed and rinsed with boiling water or sterilized with live steam. XIV. Vessels used in the manufacture and sale of ice cream shall not be employed for any other purpose by any person. XV. No member shall take back any broken package of ice cream, nor any unbroken package which contains soft

or melted ice cream. No ice cream shall under any circumstances be melted and refrozen. XVI. It is expressly declared that the object of this Code is to insure a clean product, made, stored and handled

under cleanly conditions, and no technical defect in the construction of any clause shall relieve any member of the obligation of complying with the letter and spirit of this Code in its entirety.

The Ohio
Ohio
1.

Sanitary Code.

The code adopted by
is

ice

cream manufacturers' association

the as follows:

All factories or shops shall be open to the public at

all times.
2.

Work rooms must

dust, foul
lighted, to

be thoroughly clean and free from atmosphere and contamination, and shall be well the end that there shall be no dark corners where

rubbish or dirt may accumulate. 3. One square foot of glass surface exposed to natural light, unobstructed by buildings or other devices nearer than 10 feet, for each square foot of floor surface of the work rooms must be provided. Basements shall not be used as work rooms unless these provisions can be met. 4. Garbage and all waste material subject to decomposition, must be removed daily to the outside and deposited

.

296
in a

APPENDIX

can provided exclusively for this purpose, composed of impervious material and provided with a tight fitting cover. Covers must be kept on the cans at all times except when entering or removing the material. 5. The sidewalls and ceilings of all work rooms shall be well plastered, tiled or wainscoted, or ceiled with metal or lumber, and shall be well painted, to the end that they may be readily cleaned ; and they shall be kept free from dust, dirt and foreign matter and clean at all times. 6. The floors of all work rooms shall be impermeable

and be made of cement,

tile laid in

cement, or other suit-

able and non-absorbent material, which can be flushed and washed clean with water. Floors shall be sloped to one or more drains, which must be properly connected to the sewerage system. 7. Store and storage rooms for materials must be kept clean and free from objectionable odors. 8. Doors, windows and other openings of every work room shall be screened during the fly season with screens not coarser than 14-mesh wire gauge, or in any other manner equally effective, to keep the work rooms free from flies and vermin at all seasons of the year. 9. All factories or shops shall have convenient toilet rooms, separate and apart from the work rooms, and no toilet rooms shall be within or connected directly with a work room, either by a door, window or other opening. The floors of the toilet rooms shall be of cement, tile or other non-absorbent material, and shall be kept clean at Toilet rooms shall be furnished with separate all times. ventilating flues or pipes discharging into soil pipes, or on the outside of the building in which they are situated.
shall be adjacent to toilet be supplied with soap, running water and clean towels and shall be maintained in a sanitary condition. Work room employees beginning work and after visiting toilet rooms shall wash their hands and arms thoroughly

Lavatories

and wash rooms

rooms and

shall

in clean water.
10.

No

person shall live or sleep in any building used as

APPENDIX

297

a factory or shop, unless the factory or shop is separated by unpervious walls, without doors or windows or other openings from the parts of the building used for living or sleeping purposes. 11. No horses, cows or animals shall be stabled or kept in any building where ice cream is made, unless the factory or shop is separated from the places where the horses, cows or other animals -are stabled or kept by impervious walls without doors, windows or other openings. 12. No persons suffering from an infectious disease, which can be transmitted through ice cream, shall work in

an

ice

cream manufacturing
and
shall

plant.
shall

13. All

work room employees

be clean in person

wear clean, washable clothing and caps. They shall not smoke or chew tobacco while at work. They shall not touch the product with their hands at any time. Employees may be specially designated to cut and wrap brick ice cream and to fill fancy molds and, as this work necessitates some handling of the product, such employees must be scrupulously clean and wear clean, washable clothing and caps. 14. AH wagons, trucks, drays, cans and tubs, platforms and racks, shall be so constructed that they may readily be cleaned and they shall be kept clean. Utensils must be of
at all times

smooth, nonabsorbent material, as

tin,

or tinned copper, the

seams of which are flushed smooth with solder. 15. Suitable means or apphances shall be provided for
the proper cleansing or sterilizing of freezers, vats, cans,

mixing cans or tanks, piping and all utensils used as containers for ice cream or raw material, and all tools used in making or the direct handling of ice cream, and all such apparatus, utensils, and tools after use shall be thoroughly cleansed and scalded with boiling water or sterilized with steam. The water supply for washing utensils must be free from contamination. 16. No persons shall use any vessel used in the manufacture and sale of ice cream for any other purpose.

298

APPENDIX

17. Soft or melted ice cream or any other ice cream shall not be refrozen under any circumstance. 18. Milk and cream must be stored only in clean receptaMilk or cream which has uncles in clean refrigerators. dergone various fermentations, gaseous or bitter, shall not be used in the manufacture of ice cream. Flavoring extracts, condiments, syrups, fruits, nuts and other materials used as food must be securely protected from dust, dirt, vermin, flies and other contamination, and must be kept and stored only in clean receptacles. Decomposed, decayed, fermented, rancid food material shall not be used. Ice cream must be stored only in clean receptacles in clean

refrigerators.
19. It is expressly declared that the object of this code is to insure a pure and clean product, made, stored and handled under clean conditions, and no technical defect in the construction of any clause shall relieve any person of the

obligation of complying with the letter

and

spirit

of this

code in

its

entirety.

20. All creamery and condensory operators, ice cream manufacturers, and all other dealers in milk and cream, and their customers, must cleanse all receptacles used in shipping milk and cream as soon as they are emptied, when same are to be returned by railroad, trolley or boat, in order to prevent the development of dangerous bacteria to threaten the health of the consumers of the product.

The code adopted by the Ohio association has since been adopted by the dairy and food division of the agricultural commission of Ohio. The New York association code has been adopted with certain modifications by the New York board of health.^

To make an emulsion with sweet unsalted butter and whole sweet milk, for each 10 gallons of cream use: ^
1

The apparatus used in making the test consists of an ice cream sampler, a 250 c.c. Florence flask, a 200 c.c. Florence flask, a funnel or a 250 c.c. beaker, a burette and a i c.c. pipette. All of these, except the ice cream sampler, can be readily obtained from any supply house. The ice cream sampler is a cylinder, about i^g inches in diameter (inside measurements) and about 2% inches
made of thin brass tubing. The sampler should contain exactly 50 c.c. of ice cream. For testing ice cream that has been packed and has fully hardened the sampler should be provided with a handle. This type of sampler is also preferred where the ice cream container has a small diameter. These samplers are open at both ends. The sampler for use with the continuous type of ice cream freezer or for determining the swell of soft ice cream is closed at the lower end. Making the overrun test. sample of 50 c.c. of the ice cream is obtained by pressing the sampler down into the
long, preferably

when

filled

A

hardened ice cream until it is entirely below the surface. Allow the sampler to remain there for a moment to get cold and withdraw the sampler and the ice cream which it contains. By means of a case knife or a piece of tin the protruding ice cream can be removed from both ends of the

Where a continuous may be held under the spout
tube.

freezer is used, the sampler of the freezer and filled with The sample is transferred from the sampler little difficulty. to the funnel, the stem of which is inserted in the neck of In order to readily hold the 50 c.c. of the 250 c.c. flask.
1

From

Bui. 241, Wis. Sta., Prof. G.

H. Benkendorf.

303

:

304
ice

APPENDIX
cream the opening of the funnel should be three inches
transfer the ice cream from the funnel to the 250 c.c. melted by pouring over it exactly 200 c.c. of hot

in diameter.

To
flask

it is

water. In case a funnel is not available, equally good results can be obtained by transferring the sample of ice cream to a 250 or 300 c.c. beaker. By using the hot water from the 200 c.c. flask it can be melted and then transferred to the

250

c.c. flask.

reduce the foam. All melted ice cream contains more or less foam which appears in the neck of the flask and must be destroyed before it is filled to the 250 c.c. mark. The foam can be eliminated by introducing a measured amount of ether directly into it. Usually i c.c. of ether will suffice. As soon as the foam has disappeared the flask can
filled with water to the 250 by means of a burette.

To

be

c.c.

mark.

This

is

best done

calculations are made. The number of cubic centimeters of water and ether used to bring the volume up to the 250 c.c. mark, represents the shrinkage which the 50 c.c. of ice cream has undergone when melted. Subtracting this shrinkage from 50 gives the original volume of the mix before freezing. It is then an easy matter to determine the per cent, of overrun by dividing the number of cubic centimeters of shrinkage by the number of cubic centimeters in the original mixture. This can be illustrated as follows

How

Sample used Ether used to reduce foam Water used to bring to 250 c.c. .mark Water and ether used (15.5 1)

INDEX
cooked mixtures due to acid in butter due to fruit acid due to gelatin
Dairy products as side
Defects in color Defects in flavor Defects in texture Definition of ice cream Degrees, Mann's
90 238 88
61
lines 255

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